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Trying to figure out why this engine has no compression.....I have spark, fuel and no compression. I have checked the valve lash and everything seems to be correct. So I removed the head and attached pictures to see what the experts out there think? I have before and after carbon removed. Please advise would love to hear your thoughts? I tried attaching photos but they were too large and would not allow me to attach. So I will provide a google photo link to the 8 photos.

Engine Photos

Thank you for your time helping trying to figure this out.

From the looks of the intake valve and cylinder walls, there is a high amount of dirt ingestion causing excessive wear The intake valve covered in burnt oil suggest that it is pulling in oil from the breather and burning it. The intake valve seat and valve face are showing wear which could result in the valve not seating properly and therefore not sealing against the seat. The exhaust valve looks to be sitting too high in the seat with uneven valve face to seat contact area, which could indicate either the exhaust valve is bent or the seat isn't sitting flush with the valve.

ILENGINE said:

From the looks of the intake valve and cylinder walls, there is a high amount of dirt ingestion causing excessive wear The intake valve covered in burnt oil suggest that it is pulling in oil from the breather and burning it. The intake valve seat and valve face are showing wear which could result in the valve not seating properly and therefore not sealing against the seat. The exhaust valve looks to be sitting too high in the seat with uneven valve face to seat contact area, which could indicate either the exhaust valve is bent or the seat isn't sitting flush with the valve.

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Cylinder is scored, valves need to be ground or at least lapped, probably need to replace rings. May be time to chuck it and get another engine.

Not sure why you would call this a "plastic engine". Is that because of all the dress up plastics around the engine?

Sorry, this looks like it would cost more to save than a new one likely cost. This all looks like damage from dust ingestion and overheating, especially the one valve that is indigo blue on the stem near the top.

Are you a hobby DIY repair type?

If so, Parts tree should have everything you need for this engine.

You need to look at the side of the engine for the digital etched digits to figure out the model and type information. The chassis label information usually does not apply to the engine parts.

ILENGINE said:

From the looks of the intake valve and cylinder walls, there is a high amount of dirt ingestion causing excessive wear The intake valve covered in burnt oil suggest that it is pulling in oil from the breather and burning it. The intake valve seat and valve face are showing wear which could result in the valve not seating properly and therefore not sealing against the seat. The exhaust valve looks to be sitting too high in the seat with uneven valve face to seat contact area, which could indicate either the exhaust valve is bent or the seat isn't sitting flush with the valve.

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Thank you sir for your excellent description this is why its not worth the time energy or effort to fix the internal issues it really is cost prohibitive especially if you do not have the right tools for the job.

Tiger Small Engine said:

Cylinder is scored, valves need to be ground or at least lapped, probably need to replace rings. May be time to chuck it and get another engine.

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Thank you sir this is what I was thinking as well not worth the time, energy and effort to fix when you do not have the parts of correct tools for the job. I agree with you just part out what I can and scrap.

Auto Doc's said:

Not sure why you would call this a "plastic engine". Is that because of all the dress up plastics around the engine?

Sorry, this looks like it would cost more to save than a new one likely cost. This all looks like damage from dust ingestion and overheating, especially the one valve that is indigo blue on the stem near the top.

Are you a hobby DIY repair type?

If so, Parts tree should have everything you need for this engine.

You need to look at the side of the engine for the digital etched digits to figure out the model and type information. The chassis label information usually does not apply to the engine parts.

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Thanks for the response.....these are known as plastic engines because they have plastic flywheels, camshaft and carburetor. They are not like the late 90's and early 2000 B&S steel built like a tank engine that will last 30 to 40 years! Thank you for the description and interpretation I know it must have gotten hot and one person said 600F!!! WOW!!!! Yes just self taught small engine guy flipping mowers and snowblowers I am not a small engine shop. This is not worth the time, energy and effort because there may be other issues internally that is causing the overheating. Best to part it out and scrap.

So far everyone says sayanora to this B&S. OTOH, it does not have the head gasket failure so common to the brand. The valves themself seem to have a lot of meat left on the seating area, and could be ground or lapped to improve compression. Need a picture of the valve seats built into the head for evaluation.
You should look at the installed height of the rocker arm mounting studs. They have been known to pull out of the head over time, sometimes made worse by overheating. If you have not checked, take a look down on the cylinder from above and make sure there's no clippings, etc that will block airflow over the fins, block and head both.
If you have low compression, check that the valves move freely in the valve guides. If sticky, that can make the valves hesitant to seat, causing low compression. They should slide in the guides freely, with no wobble of the valve tulip when the valve is open 1/4". A slight wobble is acceptable.
Not having any more information, I would clean the head gasket surfaces and use a new gasket to re-assemble the cylinder head, and then adjust the valve clearance.
If it does not have compression after cleaning up the valves, squirt some oil through the spark plug hole and re-check compression. If the rings are toast, oil will provide a temporary assist and compression should improve.
From the little I see, the valve seating area is not great, and the valve seats are not shown.
If you actually have no compression, and you have adjusted the valves, and they are not sticking in the guides, all that's left is the ring condition. Most times, rings will fail slowly over time, and will not suddenly cause a no-start. If the compression release built into the cam is stuck(or broken) it may hold the valve off its seat and cause no compression. B&S compression release is known to die and scatter parts throughout the crankcase with no warning and no particular reason(that I know of). That can explain a no-compression problem that came up instantly. Replacing the cam cures the problem in most cases. Bad ring sealing would also tend to cause the engine to feed oil to the carburetor leading to blue smoke when running. If you did not have blue smoke, most times your oil consumption would be low. If you have significant oil useage, rings are more likely.
tom

Another opinion

I see a perfect bore (for a mower). Have had many pushers with way worse gouges and piston rocking. Little smoking is fine. Oil is cheap guys.

One tight intake valve guide. Easily reamed out with a simple reamer tool.

Little valve guide and head lapping. New head gasket.

Minimal money and she is back cutting grass. Guy already has it torn down.

slomo said:

Another opinion

I see a perfect bore (for a mower). Have had many pushers with way worse gouges and piston rocking. Little smoking is fine. Oil is cheap guys.

One tight intake valve guide. Easily reamed out with a simple reamer tool.

Little valve guide and head lapping. New head gasket.

Minimal money and she is back cutting grass. Guy already has it torn down.

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I wouldn't really call those gouges. More like deep scratches, and like you I have seen mowers run with far worse cylinders. I agree fix the valve issue and install new head gasket and see what happens.

If you are not set up or have the experience in trouble shooting and solving the engine problems then a repower with a used engine might be sensible if the deck is in good condition. As a self described flipper you must come across beat looking mowers with working engines.

nbpt100 said:

If you are not set up or have the experience in trouble shooting and solving the engine problems then a repower with a used engine might be sensible if the deck is in good condition. As a self described flipper you must come across beat looking mowers with working engines.

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If he tore it all down as we see in the pics then he is capable of reaming a valve guide and tossing on a head gasket.

slomo said:

If he tore it all down as we see in the pics then he is capable of reaming a valve guide and tossing on a head gasket.

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I am going by what he said.

nbpt100 said:

I am going by what he said.

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Remember to lap the head and block where the head gasket sits. 220, 400 then 800 grit wet/dry paper on the garage door window. Let the paper do all the work. Spray on some Permatex hi-tack gasket spray on the head gasket. Torque bolts in 3 steps. Should be good. Recheck the torque after a couple mows.

ILENGINE said:

From the looks of the intake valve and cylinder walls, there is a high amount of dirt ingestion causing excessive wear The intake valve covered in burnt oil suggest that it is pulling in oil from the breather and burning it. The intake valve seat and valve face are showing wear which could result in the valve not seating properly and therefore not sealing against the seat. The exhaust valve looks to be sitting too high in the seat with uneven valve face to seat contact area, which could indicate either the exhaust valve is bent or the seat isn't sitting flush with the valve.

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Exactly.

Tiger Small Engine said:

Cylinder is scored, valves need to be ground or at least lapped, probably need to replace rings. May be time to chuck it and get another engine.

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Lapping just makes the seat and valve shiney.

The Bore looks to be in very good condition. Be sure Valve Guide clearance is adequate. What gauge were you using to check compression. There must have been some! Carefully reassemble, Torque Gaskets and set valves per spec. It should run fine unless there is a camshaft problem. Be sure valves are opening and closing as they should.

Montecore said:

Thank you sir this is what I was thinking as well not worth the time, energy and effort to fix when you do not have the parts of correct tools for the job. I agree with you just part out what I can and scrap.

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You ought to watch some YouTube videos of Pakistanis rebuilding engines.

To check to see if the valves are seating properly put the spark plug back in and pour some liquid in the head and see if they seal

hlw49 said:

To check to see if the valves are seating properly put the spark plug back in and pour some liquid in the head and see if they seal

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I would pay to watch him do that....

RevB said:

Lapping just makes the seat and valve shiney.

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Lapping valves also increases the compression. When valves and the seats are pitted and carboned up, it really affects the engine performance.

Lapping does not increase compression. Will not remove pits, not used for removing carbon, and has zero effect on performance. There are tons of marketing ads pushing this crap and it's all a lie.

The only value of lapping is to verify correct contact location of the seat on the valve and the width of the contact after the seat stones and valve grinder have done their work. That's it. Everything else is bullshit.

RevB said:

Lapping does not increase compression. Will not remove pits, not used for removing carbon, and has zero effect on performance. There are tons of marketing ads pushing this crap and it's all a lie.

The only value of lapping is to verify correct contact location of the seat on the valve and the width of the contact after the seat stones and valve grinder have done their work. That's it. Everything else is bullshit.

View attachment 71457

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I don’t have a valve grinder, and surprisingly, most people don’t. Most people don’t even know what valves do, much less how to lap them. When a valve moves by turning with your fingers while under spring tension, that is what lapping helps prevent. When a valve leaks when you put gas on the cylinder head to test, that is what lapping helps prevent. Nobody said lapping valves was perfect. I believe you can buy a new set of valves for a bit less than a valve grinding machine.

Tiger Small Engine said:

I don’t have a valve grinder, and surprisingly, most people don’t. Most people don’t even know what valves do, much less how to lap them. When a valve moves by turning with your fingers while under spring tension, that is what lapping helps prevent. When a valve leaks when you put gas on the cylinder head to test, that is what lapping helps prevent. Nobody said lapping valves was perfect. I believe you can buy a new set of valves for a bit less than a valve grinding machine.

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But then you still have the seat....

Agreed that not many have the stones or the tools to grind seats and/or valves....or the skill. It can be a pretty big investment and for a one time use it's better to take the parts to someone in the business of valvetrain restoration. New valves and restored seats are most likely the least expensive option if everything else is in spec. The seat to valve interface is critical as the width of the contact patch determines the amount of heat taken out of the valve head into the seat which is always cooler, relatively, especially for the exhaust valve. The intake has the benefit of a cooled intake charge. A polished valve face that is not concentric with the seat, or has slight pitting as you say, does nothing for the sealing ability, or heat transferance from the valve.

Lapping does have it's place but in the context of valves it has become the go-to to fix for problems that can't be fixed with this method. The valve face becomes concave, usually, at the seat contact area and lapping will not fix it. Only restoring the flatness and concentricity of the face will. Lapping a blind dowel pin hole to improve/increase size comes to mind to get the correct interference fit for the pin or lapping an aluminum cylinder head on a surface plate to remove warpage if the straight edge shows the surface to be not level. Lapping an iron head would take a couple of days and that is better left to fly cutting, as would the block. Generally it would be the job of the gasket to take up the slack on parts that aren't within a couple of thousandths but gaskets can only do so much.

My only point is there are expedient ways to do things that *might* get you a few more hours but since you're in there anyway, why not spend the little extra to return to as close to as-new as you can.

RevB said:

Lapping does not increase compression. Will not remove pits, not used for removing carbon, and has zero effect on performance. There are tons of marketing ads pushing this crap and it's all a lie.

The only value of lapping is to verify correct contact location of the seat on the valve and the width of the contact after the seat stones and valve grinder have done their work. That's it. Everything else is bullshit.

View attachment 71457

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You are convinced that lapping valves does no good? Then why has it been an industry standard since the first valve engines came into production? Can the whole industry be wrong?

Why is silicon carbide lapping compound used if it does not work?

Auto Doc's said:

You are convinced that lapping valves does no good? Then why has it been an industry standard since the first valve engines came into production? Can the whole industry be wrong?

Why is silicon carbide lapping compound used if it does not work?

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Not the whole industry....just the gullible part of the industry. Let's take Permatex 80037 as an example. This material is your silicon carbide in 4 mixed grits... 120, 150, 180, and 220. Ostensibly the grit size decreases as the paste is ground between the face and the seat...or so Permatex says. Where does that reduced grit go? Some embeds into the face of the valve and seat because it is way harder than the metal you're trying to remove. That would introduce annular rings in the seat and face because it's grinding, not polishing. You want to polish you better go to 2400 as a minimum. Most of your so-called "lapping" pastes aren't .

Now you have ground away material that is between the face and the seat but only at the contact point...exactly the wrong thing to do. They are not flat nor orthoganal any more. As stated previously, that may get you a few more hours but is that your goal...to get just a few more hours. You've already gotten hundreds of hours from that engine and it wasn't just a few hours at a time, it was continuous, unrepaired hours.

I'm saying, lapping, as a means to correct deficiencies, is a waste of time. There is no way you can control the angular interface and the contact surface by "lapping" alone. A stone, cut to the proper angle, is the only way to properly restore that angle.

These are mower engines not the space shuttle. Lapping seals valves to valve seats. Pretty important in the combustion process.

slomo said:

These are mower engines not the space shuttle. Lapping seals valves to valve seats. Pretty important in the combustion process.

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Whatever.

slomo said:

These are mower engines not the space shuttle. Lapping seals valves to valve seats. Pretty important in the combustion process.

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I don’t even know of a machinist in our area that will grind valves. When you factor in your time back and forth, and paying labor cost, it would be on the expensive side. Even new valves need to be lapped in to the old seats.

Tiger Small Engine said:

I don’t even know of a machinist in our area that will grind valves. When you factor in your time back and forth, and paying labor cost, it would be on the expensive side. Even new valves need to be lapped in to the old seats.

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Either have to lap the new valves into the seats or have a seat cutter set like the neway. I have the Neway seat cutter and valve face cutters, but I probably wouldn't if it hadn't been required dealer tool for either Kohler or Tecumseh. I don't remember whch.

Tiger Small Engine said:

I don’t even know of a machinist in our area that will grind valves. When you factor in your time back and forth, and paying labor cost, it would be on the expensive side. Even new valves need to be lapped in to the old seats.

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Automotive repair or engine rebuilder....most straight machinists don't.

RevB said:

Lapping does not increase compression.

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I disagree. I used to race karts with 5 HP Briggs flathead engines. I ran open class, and the engines peaked out around 6000 RPM. At the end of a race, compression would be noticeably down from the start. I would have to basically do a valve job after every race. I'd remove the head and valves. I'd decarbon the valves by spinning them in a drill press, and cleaning up with steel wool. Then lap the valves. I'd use 3 compounds. Course, fine, and polish. Re-set the valve clearances, then reassemble. Compression went way up after doing this.

RevB said:

After every race. A complete valve job. Decarbon. Ohhh Kay.

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It wasn't complete valve jobs. I didn't replace valve guides, and I didn't cut valve seats or valves. I was a teenager, so this kept me out of trouble.

RevB said:

After every race. A complete valve job. Decarbon. Ohhh Kay.

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Not like Briggs engines, well, guess they do make racing engines. Going to say they are not high rpm engines with any form of durable valvetrains. More Diesel like compared to gas motors. None are made to last 100,000 miles either like cars do.

slomo said:

Not like Briggs engines, well, guess they do make racing engines. Going to say they are not high rpm engines with any form of durable valvetrains. More Diesel like compared to gas motors. None are made to last 100,000 miles either like cars do.

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Like I said, not a complete valve job. And these were all-out racing engines. The only OEM parts were: the block, head, lifters and spark plug. The crank, cam, & piston were all high end racing parts. Racing carb & intake, too. Straight pipe exhaust. The engines turned WAY more RPMs than stock and produced WAY more power. The fuel was 100% methanol. Blown engines were not uncommon. The valves took a beating. A single race probably put more stress on the valves than a typical engine would see in its entire life. My point was that lapping the valves DID restore compression.

Here is what I learned working in a high end machine shop back when I was still building racing engines. Valves seal. Let's say they start at 100% sealing. As the valve guide wears the valve rocks in the worn guide at which point it loses some of its sealing. Carbon can build up under the valve if the seat contact area is too wide. The optimal seat contact area cuts thru any carbon that builds up. Now comes DIY home guy or small shop repair. They clean the valves and hand lap them. Maybe the sealing was down to 85% so they now have it back to 95%. The engine runs better. Did this solve the worn guide issue - no. Did this solve the seat contact area issue - no. But they charged for their services and the problems will be back but sooner this time. If they decide to replace the valve guides, the valves are no longer 100% concentric with the seats so this does not get them back to 100%. The only way to do that is to replace the guides, use a cutter or stone and a pilot in the guide to keep it concentric with the seat, then shoot the seat for 3 angles and surface the valve a little, then tip it for the same height. Nothing else will bring back 100% including hand lapping. But hand lapping is better for a while than leaving the valve and seats full of carbon. I plan to rebuild a B&S mower next spring when I heal from a heart bypass surgery. I already have the machine shop lined up who will replace the guides and do the seats and valves. They build trophy cart racing motors and are set up to do it. Hand lapping is ok as long as one understands the limitations of it and doesn't expect the engine to be 100% what it was when the guides and valves were new. If I set valves on a L-head engine, I clean the valves and seats, then hand lap. 95% is better than 85%. If I plan to rebuild an engine, then we go a different route. Most small shops are not set up to replace guides and machine shop services are mostly gone due to the throwaway society we live in.

sgkent said:

Here is what I learned working in a high end machine shop back when I was still building racing engines. Valves seal. Let's say they start at 100% sealing. As the valve guide wears the valve rocks in the worn guide at which point it loses some of its sealing. Carbon can build up under the valve if the seat contact area is too wide. The optimal seat contact area cuts thru any carbon that builds up. Now comes DIY home guy or small shop repair. They clean the valves and hand lap them. Maybe the sealing was down to 85% so they now have it back to 95%. The engine runs better. Did this solve the worn guide issue - no. Did this solve the seat contact area issue - no. But they charged for their services and the problems will be back but sooner this time. If they decide to replace the valve guides, the valves are no longer 100% concentric with the seats so this does not get them back to 100%. The only way to do that is to replace the guides, use a cutter or stone and a pilot in the guide to keep it concentric with the seat, then shoot the seat for 3 angles and surface the valve a little, then tip it for the same height. Nothing else will bring back 100% including hand lapping. But hand lapping is better for a while than leaving the valve and seats full of carbon. I plan to rebuild a B&S mower next spring when I heal from a heart bypass surgery. I already have the machine shop lined up who will replace the guides and do the seats and valves. They build trophy cart racing motors and are set up to do it. Hand lapping is ok as long as one understands the limitations of it and doesn't expect the engine to be 100% what it was when the guides and valves were new. If I set valves on a L-head engine, I clean the valves and seats, then hand lap. 95% is better than 85%. If I plan to rebuild an engine, then we go a different route. Most small shops are not set up to replace guides and machine shop services are mostly gone due to the throwaway society we live

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GearHead36 said:

Like I said, not a complete valve job. And these were all-out racing engines. The only OEM parts were: the block, head, lifters and spark plug. The crank, cam, & piston were all high end racing parts. Racing carb & intake, too. Straight pipe exhaust. The engines turned WAY more RPMs than stock and produced WAY more power. The fuel was 100% methanol. Blown engines were not uncommon. The valves took a beating. A single race probably put more stress on the valves than a typical engine would see in its entire life. My point was that lapping the valves DID restore compression.

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Methanol burns about two times slower and only has 9500btu/lb compared to 18,400btu per pound for gasoline. My guess is these were not blown or turbocharged so there is no way you could get the power you claim unless you burned 3 times the amount of methanol compared to gasoline. And...the engine's EGT would be in the toilet with methanol due to the latent heat of evaporation being about 3.5 times higher than gasoline which means everything runs far, far cooler, a blessing for valves but hell on cylinders/rings/pistons as any residual lubricating oil would immediately be washed away by the methanol. The claim of "way more power" requires at least 3+ times more methanol per intake charge than gasoline to produce the same amount of energy per unit volume. Even reducing combustion chamber volume to 13:1 won't get you there normally aspirated.

RevB said:

Methanol burns about two times slower and only has 9500btu/lb compared to 18,400btu per pound for gasoline. My guess is these were not blown or turbocharged so there is no way you could get the power you claim unless you burned 3 times the amount of methanol compared to gasoline. And...the engine's EGT would be in the toilet with methanol due to the latent heat of evaporation being about 3.5 times higher than gasoline which means everything runs far, far cooler, a blessing for valves but hell on cylinders/rings/pistons as any residual lubricating oil would immediately be washed away by the methanol. The claim of "way more power" requires at least 3+ times more methanol per intake charge than gasoline to produce the same amount of energy per unit volume. Even reducing combustion chamber volume to 13:1 won't get you there normally aspirated.

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None of that happens in typical lawn mower engines. Let's keep on track here guys.

BTW, I was "joking" about the space shuttle comment RevB. No need to refresh it again.

RevB said:

Methanol burns about two times slower and only has 9500btu/lb compared to 18,400btu per pound for gasoline. My guess is these were not blown or turbocharged so there is no way you could get the power you claim unless you burned 3 times the amount of methanol compared to gasoline. And...the engine's EGT would be in the toilet with methanol due to the latent heat of evaporation being about 3.5 times higher than gasoline which means everything runs far, far cooler, a blessing for valves but hell on cylinders/rings/pistons as any residual lubricating oil would immediately be washed away by the methanol. The claim of "way more power" requires at least 3+ times more methanol per intake charge than gasoline to produce the same amount of energy per unit volume. Even reducing combustion chamber volume to 13:1 won't get you there normally aspirated.

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You DO understand the concept of racing engines, right? High lift cams, bigger valves and valve springs, ported intake & exhausts. Steel cranks. I think the rods were aluminum. Not sure about the pistons. There were 3 classes. Stock, stock appearing, and modified. Stock is stock, except you could remove the governor, use bigger jets in the carbs, and any exhaust. Modified was, anything goes within the confines of an OEM block and OEM head. The carbs, intakes, and exhaust flowed WAY more than stock. We burned WAY more methanol than a stock engine on gas would. I think I read somewhere where the stock engines were burning about 2.5 times compared to gas. Modified was considerably more. If the stock engines were producing, say, 6.5-7HP, then the modified engines were probably in the range of 20-25.

The engines DID run cool at anything less than full throttle. I ran a few road courses, and for the last few races, I had a temp gauge. The engine would run very cool until the green flag, then I'd watch it climb every time I was on the throttle. When I'd lift, going into a corner, it would cool quickly. It would do this every lap, every turn. Also, every lap the temp would be 5°-10° hotter than the lap before. I got concerned a few times when I saw 400 at the end of a heat.

As for lubrication being washed away, you're probably not wrong. Engines were good for about one season, and we were running I/C engines with steel sleeves. I changed oil after every race, and it was always very thin. There was lots of blowby. Didn't much matter, though. Every season, the parts manufacturers would come out with a better, faster engine kit (cam, crank, piston, etc). If you didn't build a new engine with these new parts, you'd be left behind. That's when I discovered that, while cheaper than car racing, kart racing was still a very expensive hobby, and I got out.

My oil is better than your racing oil.

slomo said:

My oil is better than your racing oil.

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I don't recall, but I doubt we had racing oil. This was the early 80's, and we were changing it every race day. Probably should have changed it every heat.

GearHead36 said:

You DO understand the concept of racing engines, right? High lift cams, bigger valves and valve springs, ported intake & exhausts. Steel cranks. I think the rods were aluminum. Not sure about the pistons. There were 3 classes. Stock, stock appearing, and modified. Stock is stock, except you could remove the governor, use bigger jets in the carbs, and any exhaust. Modified was, anything goes within the confines of an OEM block and OEM head. The carbs, intakes, and exhaust flowed WAY more than stock. We burned WAY more methanol than a stock engine on gas would. I think I read somewhere where the stock engines were burning about 2.5 times compared to gas. Modified was considerably more. If the stock engines were producing, say, 6.5-7HP, then the modified engines were probably in the range of 20-25.

The engines DID run cool at anything less than full throttle. I ran a few road courses, and for the last few races, I had a temp gauge. The engine would run very cool until the green flag, then I'd watch it climb every time I was on the throttle. When I'd lift, going into a corner, it would cool quickly. It would do this every lap, every turn. Also, every lap the temp would be 5°-10° hotter than the lap before. I got concerned a few times when I saw 400 at the end of a heat.

As for lubrication being washed away, you're probably not wrong. Engines were good for about one season, and we were running I/C engines with steel sleeves. I changed oil after every race, and it was always very thin. There was lots of blowby. Didn't much matter, though. Every season, the parts manufacturers would come out with a better, faster engine kit (cam, crank, piston, etc). If you didn't build a new engine with these new parts, you'd be left behind. That's when I discovered that, while cheaper than car racing, kart racing was still a very expensive hobby, and I got out.

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You just repeated everything I said...

RevB said:

You just repeated everything I said...

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But then you go on to refute my claims of "way more power".