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My camshaft compression release gave out. Too much compression. Learned on youtube how to start it by holding hand over intake, which does work to get it started. Is there a workaround other than this to avoid camshaft replacement? I have read that new camshafts fail not long after replacement. Looking for a permanent solution.

For permanent solution buy a Kawasaki or Kohler engine that have a more robust system. Other than that the Briggs camshaft two at a time but these are not failing as bad as some would lead you to believe. It just appears that they failing more often due to the shear number of these engines. But by all means avoid the after market Chinese camshafts they are not made to specs.

I'd like to add a manual compression release like I have on my Husqvarna chainsaw and bypass the Cam mounted ACR altogether

You can try that if you wish to be getting on and off the mower everytime you want to start the engine. And if fails to start get back off again and again; unless, you someone that willing to just stand around to depress the decompression everytime.

Have you checked with the repair shops in your area. They might just have a scrap engine laying around that you can scavenge a cam out of. May be the cheapest remedy and job done right.

Laneman said:

I'd like to add a manual compression release like I have on my Husqvarna chainsaw and bypass the Cam mounted ACR altogether

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It will work sort of.
Most times it will not turn off by itself
It was a common trick with dirt bikes that had no kick starter running on high compression dope engines back in the 80's before rollers became available at a reasonable price .

On mine I would just open the hood and muscle the engine past the compression stroke then hop back on the seat and start it. I did disable the seat switch so I could get off without have to go through that again. Did that for 10 years. I am 70, last year I got a new mower, my third ever, JD 130E. I have lived on the same property for fifty years and yes, I am cheap.

Laneman said:

My camshaft compression release gave out. Too much compression. Learned on youtube how to start it by holding hand over intake, which does work to get it started. Is there a workaround other than this to avoid camshaft replacement? I have read that new camshafts fail not long after replacement. Looking for a permanent solution.

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I used that "covering the intake' hack,until I bought a new engine. However, as was pointed out here, there are broken pieces inside the engine that may not play nice with other parts in there. There are many 31R Briggs engines out there that have failed for different reasons besides the compression release breaking. I don't know enough about the differences of the cams from 17hp 17.5hp and 18 and 19hp,so those cams may not interchange from one hp to another.

Thanks for the replies and ideas. I watched a cam replacement video and the oil sump did not look very deep, meaning the broken pieces could get into some moving parts. Think I'll just get the OEM camshaft and do it right. I just bought the mower for $200 as a no start. It's a 46 inch Craftsman in good shape, maybe worth the price of a new cam.

SamB said:

I used that "covering the intake' hack,until I bought a new engine. However, as was pointed out here, there are broken pieces inside the engine that may not play nice with other parts in there. There are many 31R Briggs engines out there that have failed for different reasons besides the compression release breaking. I don't know enough about the differences of the cams from 17hp 17.5hp and 18 and 19hp,so those cams may not interchange from one hp to another.

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All of the 210000, 280000, 310000, and 330000 series OHV engines use the same camshaft but for some reason the 310000 and 330000 are the engines that these are constantly failing on . Now take that with a grain of salt as these are also the most installed Briggs single cylinder rider engines so the volume of them out there is huge. The 793880 (superseded to 84005207) is definitely a weak point of these engine along with the head gaskets. Since the OP has a 310000 series I highly recommend changing the head gasket too while he/she is replacing the camshaft.

After reading the previous postings, I'd like to add my two cents worth. In 2024, the original (1994) B&S engine on my DR Field and Brush mower failed. The local (Virginia) shop I've used for years said they could no longer get the needed parts and recommended that the engine be replaced. After some days of searching, the shop told me that the Vanguard 190000 was the only engine they could find with the correct "form factor." I had them order and install one. Apart from being a bit over-powered, the mower ran well for several months. Then that engine failed: too much compression to be started by pulling the starter rope. The shop picked up the mower, took a look, and said that it needed warranty service. Since they were not an authorized B&S shop, I had to take it to a shop in Maryland. That shop diagnosed a broken compression relief device and repaired it under warranty, saving me over $400.00. I used the mower the rest of the year without any problems. I went to start it a few weeks ago and found the rope almost impossible to pull, the same symptom I had earlier when it failed the first time. I can hear the cylinders start to fire and get some smoke, but nothing moves. The warranty on the original repair has expired. Since I use the mower only about 25-30 hours a year, I really don't want to have the engine rebuilt again. Is there some way to manually release compression so I can pull the starter cord rapidly enough to get the engine started? Thanks.

The Briggs Vanguard comes with a three-year warranty. if the original repair was done in 24, then it is covered to 27. They are incredibly good commercial-duty engines. So, unless it was starved for oil (such as tilting beyond limits or running low) and it has been maintained, it should be covered. Contact your dealer, and if you can't get help from them, ask for the local Briggs representative's contact. Another thing to check, pull the spark plug out and pull the engine over radidly and see if blows and gas out through the spark plug hole...Just thinking it could be a bad needle valve in the carb leaking fuel into the cylinder.

kbowley said:

The Briggs Vanguard comes with a three-year warranty. if the original repair was done in 24, then it is covered to 27. They are incredibly good commercial-duty engines. So, unless it was starved for oil (such as tilting beyond limits or running low) and it has been maintained, it should be covered. Contact your dealer, and if you can't get help from them, ask for the local Briggs representative's contact. Another thing to check, pull the spark plug out and pull the engine over radidly and see if blows and gas out through the spark plug hole...Just thinking it could be a bad needle valve in the carb leaking fuel into the cylinder.

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Thanks for the reminder about the warranty period. I pulled the plug as you suggested and, of course, the engine turned over easily, but no gas came out of the plug hole. I put the spark plug back and took off the air cleaner. Some people have suggested elsewhere online that covering the air intake could help with starting so I thought it worth a try. Wearing a rubber glove, I covered the air intake and tried to start. No luck, though there was suction on my glove. I then phoned the dealer who repaired the engine and the tech there believes it might be a carburetor problem and suggested spraying Crud Cutter into the air intake. That's my next task. Will follow up with results.

I've installed 2 84005207, no failures yet, only been a year or so I think.. so take that for what it's worth

JEHunter said:

Thanks for the reminder about the warranty period. I pulled the plug as you suggested and, of course, the engine turned over easily, but no gas came out of the plug hole. I put the spark plug back and took off the air cleaner. Some people have suggested elsewhere online that covering the air intake could help with starting so I thought it worth a try. Wearing a rubber glove, I covered the air intake and tried to start. No luck, though there was suction on my glove. I then phoned the dealer who repaired the engine and the tech there believes it might be a carburetor problem and suggested spraying Crud Cutter into the air intake. That's my next task. Will follow up with results.

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DO NOT spray crud cutter into the intake. Try some starting fluid or carb cleaner. No idea why he would have told you to do that. I hope he doesn't work on equipment. LOL Also, I got confused regarding the warranty because I read the post at the top of this page and forgot you don't have a Vanguard...so sorry.