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View Full Version : Valve Job??


turfinator
05-05-2002, 11:29 AM
I've got a 5hp engine on my Power Rake that has become almost impossible to start. I change the filter, plug and oil often. I even took the head off and removed the carbon and checked to make sure the valves were operational. I have tried starting fluid with mixed results. It seems to take alot of attempts to start it. I've had better results trying to start it with choke on then off, back and forth about 20-30 times with the filter off. The starting fluid doesnt seem to make too much of a difference. When I pulled the plug it seems to be getting a decent spark. When pulling the starter rope the valves seemed to operate properly. I also cleaned them up as good as I can. Unfortunately all of my mechanical experience has been with 2 stroke dirt bikes so I'm not at all familiar with valves. I have gone over everything I can think of with this engine, so I'm left guessing its needs a valve job. Is there anywhere on-line that explains this procedure. Can it be done without taking it to a shop? Sorry this is so long winded but I just replaced one engine and hope I dont have to do the same with this one

Any
suggestions??
:confused:

sdwally
05-06-2002, 09:20 AM
Usually behind the carb is a plate the allows access to the valve springs. Check the clearance, about 0.007" intake and .011" for exhaust. You will need a small valve spring compressor, coarse and fine lapping compound, and lapping tool(stick with suction cups at each end.)
Adjust clearance by using a grinding wheel. While spinning the valve, lightly touch it to the side of a grinding wheel on a bench grinder. Only remove small amounts at a time.
Use the coarse lapping compound on valve seat area to start. While spinning the tool between your hands(back and forth), apply light pressure to lapp. Occassionly rotate valve about 1/3rd turn and continue lapping. After a rotating valve completely, clean seat area with dry rag, seat area should be completely polished, if not continue with course compound.
Once full contact is aquired use the the fine lapping compound in the same manner.
Recheck clearance. Replace valve springs(keep valve spring separated(intake and exhaust springs are normally different.)
Best of luck.

Russo
05-06-2002, 11:28 AM
Holy moly. I believe I would check for water in the gas, or worn seat ( or diaphram ) in the carb, or fuel filter, or some simpler things to narrow it down before I voted for a valve job. Have you checked this stuff? I concede that it appears that you know about engines than me, but I didn't know if " I checked everything else" included these items.

floydboy
05-06-2002, 12:20 PM
Have you checked the flywheel key. If it is bent, worn down or damaged in any way it can cause the unit not fire at the right time. There are only 3 things that run an engine. Fuel, Fire, Compression. Check each one.
Floydboy:blob3:

khouse
05-06-2002, 11:29 PM
remember to remove the carb from the tank as the tank has a built in bowl in it. This may be where the water and trash have landed. There is really 2 diaphrams to this carb. You should buy a carb kit and install it to help narrow down a fuel problem. This is assuming that it a Briggs?

turfinator
05-08-2002, 03:10 AM
Ive removed the carb bowel as well as the bowel retaining nut and cleaned both. I havent removed it from the tank though. What type of diaphram is located in the tank? Are there any schematics available for this and the carb. I know I need to buy a manual. This is the type of engine:
http://www.briggsandstratton.com/om/pdfs/274778.pdf
Thanks

khouse
05-08-2002, 09:25 AM
There is no fuel bowl on that carb. Where the carb mounts to the tank - that's where the diaphram is. You must remove the carb from the tank.

turfinator
05-08-2002, 04:53 PM
Your right I got this motor mixed up with my IC motor that was giving me the same problems. Everything else is accurate minus the carb info. Once I remove it from the tank what is the proper method of cleaning?

khouse
05-08-2002, 07:24 PM
Get the carb kit first. You may need to scrape the resivour out with a dull screw driver or small wire brush. Then spray it out with brake cleaner. You may need to do the same with the tank.

turfinator
05-08-2002, 08:48 PM
Where is the resivour you are refering to?

Fish
05-08-2002, 09:16 PM
Just so we all know what engine you are talking about, post
the engine's model, type, and code numbers.
Fish

turfinator
05-08-2002, 09:40 PM
Model# 135202
Type# 0142 01
Code# 9408 1729

turfinator
05-08-2002, 09:42 PM
Sorry the code# should have read 9408 172D

Fish
05-08-2002, 10:01 PM
What khouse is referring to is a bowl in the top of
the tank, directly under the carb. On real bad
cases, rust pinholes can develop in this bowl making
for hard starting. Remove the tank and carb and
disassemble it and make sure your problem is not
here first. To do a proper valve job requires special
tools anyway, lapping does not give a good repair.
Fish

TFL
05-08-2002, 11:07 PM
Fish is right must have a valve machine to get right angle. I have one they are not cheap. take it to a qualified machine shop. it shouldn't need any of this unless the engine has at least 10000 hrs on it

khouse
05-10-2002, 12:16 AM
go here and scroll down to your carb and you'll see what's under it. This exploded veiw will help you. If this link doesn't work the go to www.briggsandstratton.com and go to (my engine) and fill it out with your #'s to bring it up.

http://www.briggsandstratton.com/ipl/pdfs/MS2810.pdf

turfinator
05-10-2002, 08:59 PM
Thanks everyone for your input. Seeing that we got 21 cm of snow yesterday I had some time to tinker with it.(Gotta love Winnipeg in the spring) I cleaned out the pick up filter. It was pretty dirty, and I repalced the diaphragm. It seemed to be stretched a bit. I also took off the flywheel to check the key and it was fine. I tend to believe at this point it must be the valves. It still doesnt start without pulling it for a 1/2 hour when cold. I'm starting to look like Popeye on my right side.