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Model 445777

Type 0172 E1

Picked up a free Craftsman riding mower with a 21.5 HP Briggs Twin Intek.

Engine cranks slow, both pistons do move.

One side is missing push rods and valve cover. I'm guess it bent a push rod and previous owner stopped using it.

My question is: Is this engine worth fixing up? I know inteks have a really bad reputation.

Look at the head with the missing push rods. Look inside the valve springs and see if the guide sticking up is the same height on both intake and exhaust if one is really high and will hit the valve keeper when that valve opens, you will have to replace the head. the other thing is that engine likes to eat push rods, meaning there is an oil passage big enough for the push rod to slide though and end up in the crankcase. Have found them to break governor gears, break the compression release on the camshaft, or find them wrapped around the camshaft.

ILENGINE said:

Look at the head with the missing push rods. Look inside the valve springs and see if the guide sticking up is the same height on both intake and exhaust if one is really high and will hit the valve keeper when that valve opens, you will have to replace the head. the other thing is that engine likes to eat push rods, meaning there is an oil passage big enough for the push rod to slide though and end up in the crankcase. Have found them to break governor gears, break the compression release on the camshaft, or find them wrapped around the camshaft.

Click to expand...

Before your response I adjusted the valve lash on the #2 cylinder and it started cranking fine. I ran it for a few seconds with carb cleaner.

On the #1 cylinder the intake valve guide is sticking up much further. Should I remove the engine to see if a push rod is inside the engine?

There is a chance it is in the crankcase, so you are going to need to remove the engine and the engine sump to go exploring.

You do need to see if the missing push rod(s) are in the crankcase. A new sump gasket for this engine is about $24. As for the head, simply pushing the guide back in will not work. I can tell you how to fix the guide however without replacing the head. Address below, out in proper format and remind me engine model number and what you want.

Walt Conner
wconner5 at frontier dot com

When my Intek 24 ate a pushrod it was "digested" by timing gear and came out in two pieces. Pics on this site. I did not crack check the crank gear, but the engine has run well for the last 8 years. It runs on the edge of too hot so I have an oil cooler and temp gauges to monitor. Run 5w-30 Mobil 1 only because it is common to a car I own. The engine will use/throw the thin oil a little . You cannot replace pushed guides only the head. My theory is Briggs sometimes loses control of their casting vendor or the head softens from being over heated, IL ENG is tired of my preaching, lol.

I'm watching Motoman. It is mostly due to overheating of the aluminum in the heads. Could be some variation in quality control also. Could all be within specification but slight variations in metallurgy could make some parts more sensitive than others.

I'm going to buy a good used cylinder head. I've seen a few for sale on ebay that include other parts I need.

The mower it self needs the steering gear replaced, blade engagement cable, new blades.

I will be selling the mower, once everything is in good working order.

To give Briggs fair play. My experience early soured me on more Briggs, but after this run I've had with the Intek I'm somewhat forgiving, especially since I talked to a local Husqy dealer who told me Kawasakis push guides too. Boiled down, I find myself looking at the black Crafstman garden tractors with the "Endurance Engines" which may be just marketing gobbly guk. I do not know. But the Endurance Engine hype promises better fan and that should be worthwhile. BTW the Kaws pushing guides suggests heat as the universal culprit, and...maybe the same casting house makes Briggs and Kaw heads. Would not surprise me.

I have seen pushed valve guides on Kawasaki, Briggs, and Kohler. Kohler included the Command, Courage, and this past year an Aegis after the water pump failed. I am sure it is heat related, since the guides are pressed in, and the aluminum expands at a different rate that the cast valve guide.

Other than the liquid cooled Aegis the rest had mouse/chipmunk nest, or other debris blocking the cooling fins.

I once had a English 1558 Lotus engine whose valve guides had a circlip to stop movement of the guide. I cannot remember if the clip was bottom side (stopping upward movement), or top side. Wonder why that technique is not apparently used? Also if guide movement is always upward why not circlip the bottom side? Maybe cause once the head grip is lost the guide will move in either direction it can and mfgrs figure less damage upward?? That direction " only "destroys the cam lobe as it slowly grinds down to a perfect circle. Also on the subject of pushrods in sump...When I opened the engine and could not find the pushrod it took a number of self arguments that the pushrod could possibly have gone into the sump thru the tiny oil passage hole, but it did. I remember that Briggs had purposely left in some casting spider webbing accross the hole, which I cleaned out to improve oil "mist " return. Crazy

I installed a good used head today. Starts up really good, and it sounded normal. A little smoke came out of the carb not a big amount. No smoke comes out of the dip stick hole. It's been sitting for a at least a year I would guess.

I'm going to give the engine a good cleaning now and oil change.


Short video of it running https://youtu.be/ABnkMhMdGJ0

Ok there seems to be white smoke (maybe vapor?) coming out of the carburetor, after I turn off the engine. The engine runs good, no surging or anything. Any ideas what would cause this?

If it is vuel vapour it is perfectly normal and the result of the decompressor allowing fuel vapour to flow back out the inlet valve.
Get your nose in there and have a whiff you should be able to smell the difference between fuel vapour & oil smoke.

Just a small sniff, as petrol sniffing can become adactive.:confused2:

I love it when Berts gets scientific...:laughing:

Well the other way is to use a match but singed eyebrows are not fashionable at the moment.
We have a big problem with dissadvantaged bored indiginious youth getting off sniffing fuel
It is actually addictive and usually results in severe brain damage

bertsmobile1 said:

If it is vuel vapour it is perfectly normal and the result of the decompressor allowing fuel vapour to flow back out the inlet valve.
Get your nose in there and have a whiff you should be able to smell the difference between fuel vapour & oil smoke.

Just a small sniff, as petrol sniffing can become adactive.:confused2:

Click to expand...

It was vapor.

It started running really rich now. Will be taking the carb off today.

I held off because of advice by more experienced folk. Now I will add that we used to shake brass floats to see if they contained gas reducing their buoyancy . And it was possible for floats to be so full no shaking would detect a full-up float which would not float properly to close the inlet needle and seat. A "stroke" spec would always be called out for the total droop of the float (inlet open time) by measurement from the parting edge of the carb casting to max droop. Then the "cut off" dimension from the same surface to when the needle just touched the closing tang on the float. Hope that makes some sense since I have not fiddled with the carb in question. Also I remember several times when a tiny piece of gas line rubber was lodged against the float needle, sometimes jamming it. Not visible. This piece was from the push-on ferrule type connection such as the inline filter. Especially if the line was old and soft or diameters were causing excessive mating force. Bla Bla Bla:confused2: