Search results

If you still see cross hatching and have 90 PSI compression with a compression release properly working, the rings are probably fine. However, if not and B&S does not sell them any longer, you may find some by a ring maker that are close enough to be file-fit to size. See, for example...

Even if you used a compression gauge with a hose a mile long, the reading would be the same as one with a short hose like the one in the picture. It just would take longer to measure it. Think of it as inflating a tire: with the same supply pressure, the same tire pressure will be reached, but a...

In a way, the inductively coupled hour meters are superior in concept to a battery-operated one because it is possible to leave the key in the "on" position by accident and count hours when the machine is not running. Of course, they are better only if they work.

For anyone not aware, there are hour meters that can be installed on spark-ignition engines that only need a single wire put near a spark plug wire to show cumulative hours. The electrical energy going to the spark plug is inductively coupled to the wire, which triggers the meter to count run...

I think "standoff voltage" would be more accurate than stress. From an electrical perspective the idea is that the insulation will be more likely to fail due to the need to withstand greater voltage. From your later comments, you seem to agree. Widening the gap increases the breakdown voltage...

For everyone's reference, here is the PET-4000 in action: I am curious. Would you describe how it would have caught this problem?

ANSWER In the first post, I described two test, one for ignition, and one for compression. The ignition test needs to be looked at carefully. Ignition test procedure: Remove the spark plug, hold the body of the plug against the cylinder head, and pull the recoil. Ignition test result: There...

This engine has a date code of 0702. I think flux capacitors are only used on newer models. Besides saying that many things were OK, I mentioned two tests. What does each of those tests *guarantee* to tell you and not tell you about the condition of the engine?

Maybe a bit closer in format to What's my Line?

No.

Probably not. I was originally thinking that I would give the game about a day. By now, I have explicitly stated that most of the parts were OK. There are not all that many things left to consider.

I was actually thinking some strange carburetor problem myself when it first happened and I did the initial tests I described. However, I could not come up with a reasonable scenario either, and as it turns out, the carburetor was OK. I was suspicious of the coil thinking an internal connection...

It is unrelated to the issue, but I use this mower as a cheap brush hog sometimes. After going through blade adapters on a routine basis, I made a two-part adapter that allows some motion when there is a hard impact. It is much easier on the internals, and I have never lost another blade adapter...

Now you are thinking out of the box, and that will be helpful. But no, the throttle was OK. HINT: One of my original tests would technically be called an asymmetric test. An asymmetric test will either find if something is OK or bad but not the opposite. For example if you look under your car...

The blade and blade adapter were OK. However, that is a reasonable guess. The standard flywheel on an engine made for a mower has very little inertia, so without the added intertia from the blade, starting would be difficult. Maybe it would not even start. I am unsure on that.

HINT: You are drawing more conclusions from the tests I described than they gave. Regarding ignition timing, there was no internal damage, change in the timing gear alignment, or damage to the flywheel key, so ignition timing did not change after the mower met the log.

I will give the answer tonight (assuming nobody guesses correctly before then) in case anyone else wants to venture a guess or ask diagnostic questions before then.

The recently-sharpened blade tried to split the log for me but did not have enough power behind it to do the job, similar to my experience below, although that was different piece of wood and the mower was OK after I was able to retrieve the blade.

The engine internals were all OK. There was no damage to the timing gears, piston, valvetrain, crankshaft, or connecting rod.

That would be the first place to look since it probably is the most common problem when a mower hits something it should not, and hopefully the crankshaft does not get bent. I would not have started the thread for a ho-hum problem like that. I had mentioned in the initial post that the flywheel...

To clarify, I do not mean a manual compression release like on a chainsaw but one that is part of the camshaft.

Yes. I think just about all of the modern 4-cycle small engines have one. On this engine, it opens the exhaust valve a little.

No. They are fine. I think that would have lowered the compression reading. 86 PSI is about as high as those engines get with the compression release.

I had an issue with a fix that seemed uninituitive enough to me that it might have some value here. Anyone interested in venturing a guess on what was wrong? Let me emphasize that I have fixed the issue, so the thread is more along the lines of entertainment/education vs. helping someone...

The road to Hell is paved with good intentions. Old head gasket or new one, this thread, while interesting, is becoming tangential to helping Paul's Toro get his mower running smoothly. On that front, while checking the the governor by manually operating the throttle valve as I had suggested...

I was trying to pass along what I considered good advice, not start a war. The L-head B&S engine seems very tolerant of used head gaskets, and as someone mentioned, the bolts usually work loose. I have never had a reused head gasket fail, but you need to use a little common sense when deciding...

If it is working OK under load, that would make valve and ignition issues less likely. On the other hand, it is not that hard to get to the valves on this engine, and it never hurts to make sure they are moving freely, lap them, and adjust the clearances (0.005"-0.007" intake and 0.007"-0.009"...

Get and installpaint.net (https://www.getpaint.net/download.html) and then open and save the picture file using a lower resolution to reduce the size of the picture. Check basic things like a clogged air filter and valve clearances. Make sure you are getting good fuel flow. Do a compression...

Ignition timing may be an issue with running, but it does not affect compression. Maybe it is a long shot, but here is what I found when I had a 120000 series engine that would not start and had virtually no compression. The picture shows things exactly as they were when the head was removed.

It could be a copper version of the 493823 spacer that is needed for some applications. Looking at the picture, the 493823 spacer is clearly not copper, but I did notice that the complete gasket kits have the copper washer and one that is the same size that is made of fiber.

model 123K02-0181-E1 02060756, B&S model number 590508 for the kit, although it is not an OEM gasket set. I do not see this washer in the picture of the kit from B&S but have gotten it in other aftermarket kits also. In fact, all of them on eBay seem to have the copper washer...

After sleeping on it, thanks but... The float bowl nuts on these engines always have small fiber gaskets. This one is larger. More accurate dimensions are 0.32 inches ID X 0.55 inches OD. Also, the kit does not contain any other carb parts. Any more ideas?

Thank you! I was not thinking at all about the carburetor and could not see where it might go.

Hi All, There is a small (about 3/8" center hole) copper washer included in the gasket kit for a 190 cc (120000 series) B&S engine. Would someone please tell me where it is supposed to be used? Thanks very much!

After sleeping on it a bit, it seems possible that the bushing was intended to be installed with a 1 mil interference fit. Perhaps it was made 1 mil larger than 1 inch so that a reamer with a standard dimension of 1 inch could be used.

Thanks again for all of the information. I was thinking of using a piloted reamer with a new sump for alignment. That should hopefully provide sufficient accuracy. The mag-side journal is 0.874" while the ID of the 796961 bushing is 0.878" (and 1.001" OD). Journal bearing clearances are 1.5 mils...

Thanks for the information. I did find the 19158 tool listed in a B&S Service Tool Catalog uploaded 7 years ago at https://www.yumpu.com/en/document/view/23866457/briggs-stratton-service-tools-catalog where it lists the kit as being for engine models 6, 8, 6B, 8B, N, 90000, 100700, 110000...

I found a replacement magneto-side bushing for my 124T02-3853-B1 Briggs and Stratton engine in the parts list for that engine. (The part number 796961.) However, when I disassembled the engine, I saw that the bearing was integral with the casting. The manufacturer's manual for the 120000 series...