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Hey All,

New to the forum. I have a 7 hp craftsman pressure washer with a briggs OHV engine on it. This is about 6 years old, and it has been giving me trouble for quite some time. As of late, I am simply unable to pull the engine to start. It definitely seems and sounds like a compression issue as I can pull slowly and hear and feel the air in the engine, and then move to the next stroke.

So, after lots of research, I came to the conclusion that this is likely valves being off, or a broken compression release. Since I'm not sure about the compression release, I decided to tackle the valve adjust (what an oily mess). I'm at the point where I'm trying to find 1/4 past TDC, and also adjust the valves. What is driving me crazy is this torx (or hex?) screw in the center of the valve rocker adjusters. I can not find a torx or hex that fits in there! Is it some special non-standard size? I'm somewhere between too small and too big with I think was a T10 or T15 torx. I have several torx and hex sets, and i have gone through nearly all of them. It just doesn't make sense. Never seen a bolt head this size. I also don't understand what that screw does, as I can still crank the adjuster nut up/down and even remove it.

Thanks much for any help on getting this engine running again. I really need the washer right now.

I have adjusted valves on Briggs engines and I can say I don't remember ever having a problem with wrench sizes. You should be able to tell the difference between hex (allen) and torx because they look a lot different. I got thinking about my torx sets which I have several sets of. All my sets go 10,15,20 etc. like you said so I don't know what you have? There is a lot of Briggs experts so maybe one of them can help you or like you said a special wrench??

tucolawn said:

Hey All,

New to the forum. I have a 7 hp craftsman pressure washer with a briggs OHV engine on it. This is about 6 years old, and it has been giving me trouble for quite some time. As of late, I am simply unable to pull the engine to start. It definitely seems and sounds like a compression issue as I can pull slowly and hear and feel the air in the engine, and then move to the next stroke.

So, after lots of research, I came to the conclusion that this is likely valves being off, or a broken compression release. Since I'm not sure about the compression release, I decided to tackle the valve adjust (what an oily mess). I'm at the point where I'm trying to find 1/4 past TDC, and also adjust the valves. What is driving me crazy is this torx (or hex?) screw in the center of the valve rocker adjusters. I can not find a torx or hex that fits in there! Is it some special non-standard size? I'm somewhere between too small and too big with I think was a T10 or T15 torx. I have several torx and hex sets, and i have gone through nearly all of them. It just doesn't make sense. Never seen a bolt head this size. I also don't understand what that screw does, as I can still crank the adjuster nut up/down and even remove it.

Thanks much for any help on getting this engine running again. I really need the washer right now.

Click to expand...

Whats your model type code?

You could try the valves but my thoughts would be a problem in the pressure washer pump before the engine. ( I could be wrong)

The centre lock screw could be a 4 mm allen key screw if the 20 torx does not fit in.

slacken the middle screw off then turn the adjuster nut which I assume is a 5/8 socket or spanner size?

Follow link and bottom of page to adjust.
Servicing Engine Valves | Briggs & Stratton

Gaps could be 0.004" - 0.006" depending on model.

OK I understand the wrench's now. Allen wrench sets come in two sizes MM and SAE.

btw, it is 1/4 inch past top dead cylinder, not 1/4 revolution.

Thanks for the quick replies!

Where can I find the model type of this briggs engine?

Also, I hear what you guys are saying about the allen/torx, but I guess at this point I need exact specs, because I've tried everything I have and I do have complete sets of both hex keys and torx. Is this an american and metric sizing with hex keys or torx that I might be missing? Pretty much everything I have is metric, as I rarely need American sizes to work on most of my stuff.

About the pressure washer pump being the culprit, I wonder if this is true. The washer had been doing that rough idling (when not operating the pump / trigger off), where it would engage and disengage constantly until the trigger was pulled and then it seemed to work OK. The reason I thought it was the engine was because of the feel of the pull. I can pull it, but if I try to pull fast , it will stop up. I then have to keep steady pressure on the cord as I can hear air moving, and then I can pull further. Also, if I take the spark plug out, the engine turns very easily. It was after I pulled the plug and was able to pull easy, that I figured it was some engine compression problem.

reynoldston said:

OK I understand the wrench's now. Allen wrench sets come in two sizes MM and SAE.

Click to expand...

I bet that's it if it's a hex key , and not a torx. So many video show those screws being torx. I have stared at these tiny bolts in the sun and everything, and I still can't tell for sure. I think I see a sharper point which would indicate torx, but since torx just just one size range (i think), the it must be hex key.

Engine number should be either on the valve cover or a plate over the muffler. Post them and I will find you a manual. Most newer Briggs use Torx lock screws.

My money is on torx

Fish said:

My money is on torx

Click to expand...

He was saying size between 10 and 15. now that is small for torx. Now I have several sets of torx bits and just don't see anything in them sizes? What sizes do your torx bits come in between 10 and 15? I couldn't find anything on the web also? I have never looked into this before seeing I must never needed them sizes? Now we are talking about the male torx bits not the female style sockets which use different size numbers.

I can not start my pressure washer without holding the trigger open on the wand. Too much pressure to pull the rope.

Torx tips are tapered, it is likely the t15, just the tip or fastener is likely boogered up a little

OK. Finally got the model of the engine, and also figured out the screw problem. It is indeed an SAE hex key (allan) bolt.

The engine model is 129612 0114 E1. I've been able to find parts sheets, but no manual or specs on the valve adjustment. Thanks for any help on that!

This manual should help you out.

http://dl.dropbox.com/u/12502267/B&S Service Manuals/10_276781SingleCylinderOHV.pdf

this might be a longshot,if the crankcase isn't full of gas,ill almost bet the pump is bad

tybilly said:

this might be a longshot,if the crankcase isn't full of gas,ill almost bet the pump is bad

Click to expand...

could the pump be bad, but still have the symptom where the start cord will pull freely on when the spark plug is out?

Also, I'm thinking the valves are not the problem. After seeing the specs in the manual, it seems they were pretty close to being in spec. I've read that the compression release mechanism on the cam can actually break. I don't know what it's going to take to check that though. Wouldn't that require complete engine disassy?

Rotate the flywheel so that the piston is at top dead cylinder, and both valves are fully closed{rocker arms loose}. Measure the clearances using feeler gauges and
post them here, I am betting that they are too great, thus causing your problem. That is your next step.

Fish said:

Rotate the flywheel so that the piston is at top dead cylinder, and both valves are fully closed{rocker arms loose}. Measure the clearances using feeler gauges and
post them here, I am betting that they are too great, thus causing your problem. That is your next step.

Click to expand...

Thanks, and I did get the engine to finally allow me to pull over with the plug in , by tightening those valves.

I thought I had this problem fixed, but after putting it back together, I am not able to get any starting action with the engine Also, it feels now like there maybe not enough compression. I do have spark, and I used a lot of starting fluid in the cylinder and intake. Didn't help at all.

Not sure if this is possible, but I think I may have adjusted the valves to stop the jam up, but may have not adjusted them properly and caused another problem. I'm still confused on the whole TDC and 1/4 past TDC stuff as I don't even know what I should be using for this engine. Also, the feelers I have only go down to .006. So, how I adjusted the intake (top I think) was to tighten down on the .006 feeler until it would barely move.

The only other thing I'm puzzled by is the engine oil. It seems to be overfilled and maybe filled with gas. I lost a LOT of oil on the floor when I took off the valve cover (more than they say should come out), and still the stick is showing slightly above full on the oil. I also had oil literally shoot me twice in the face when I was pulling the rip cord with the plug out (shot from the cylinder). Now, I did have the engine tipped backwards on edge a lot, so that probably causes some problems like this. Not sure what any of this means, but would appreciate any more ideas. In particular how I can make sure those valves are adjusted within the proper spec. Thanks!

Get a better/wider range of feeler gauges, and adjust the engine correctly!!!!! Google some vids of the procedure!!!! Fix it and be done!!!!

You have already answered your own Question. The oil is so over full that it shoots out the spark plug hole and is still over full.
Does it smell of gas?

If the crank case is over full the engine will not turn over as it should.

Change the oil and get the valves close. It will run if they are close

All Briggs engines should be adjusted 1/4" passed TDC.

OK. Got it!

I think they were too "tight". This time I started it up with the cover off, and it seems to be running better than before. These engines are pretty sensitive on the valve adjustments, and that 1/4 past TDC. I kept cycling it and feeling with the screwdriver to try and get it right. Think I'm about .005 on the intake and .0010 on the exhaust. Thanks!