86 2PG will not start after overheating(?)

[saunteret]

Folks, I am stumped at the moment.

Last week my kids came into the house saying that the golf cart quit working. So, I walked to the back of the property (things always seem to happen the furthest point away from the house ) to check things out. The engine appeared to be hotter than normal, so I let the cart rest and then fired it up and started driving home. I took the seat off and was watching, and it appeared that the drive belt had stretched out and the engine was working extra hard and getting hot. I parked it in the barn, ordered a new belt and waited for UPS to deliver a new one. Once the new belt got to the house, I put it on, and it just will not start. Period, except for a backfire after resting all night with the plug out.

So far, here is what I have looked at/done:

- New spark plugs (BP5HS)
- I have good spark, looks nice a blue and lots of them.
- tried opening and closing the gap (.015 to .030)
- cleaned all electrical connections/grounds
- new battery (had a spare laying around)
- Spark plugs are wet after starting
- Turning the engine over for a period of time, fuel will come out of the exhaust pipe (muffler has been removed and BBQ'ed) Muffler is still off.
- Pressurized the fuel tank, getting fuel through lines, put new lines on it anyway
- Fuel pump works, spurts a good stream
- choked with hand over carb, can feel suction
- if I let it sit overnight, it will backfire once or twice but that is it
- Pulled engine, cleaned it off good, and didn't notice anything out of sorts
- tightened the head bolts about a 1/8 turn

It was running fine up until I think the kids overheated it due to a slack drive belt. I guess the next thing is a compression test.

My wife has a slight disability and uses our cart on the farm, and I need to get this going. Heck, we all use it and need to get this going.

Anyone have any ideas? The engine is just sitting in the cart and I can have it out in a matter of minutes. Maybe the seals? The seal behind the drive clutch looks seated good, and maybe I need to check the one behind the flywheel? Since the engine is virtually pulled, maybe a good time to go ahead and replace them. I assume pull the clutch and flywheel and press new ones on?

Thanks in advance,

Chris

[redcloud]

Do a compression check as that will give a wet plug. Should have at least 90#s to 125# anything below will give hard to no starts as the pressure goes down.
Now another thing that has been said on this forum is a bad diaphram in the pump that allows fuel to seep into the block after shut down filling the block with excess fuel and causing all kinds of issues.
I think that you may have a bad piston for my thoughts though based on over heating it that could have taken out a ring.
If you have oil injection, make sure you are getting oil into fuel intake as that can heat up an engine and take out rings.

[saunteret]

Thanks, redcloud.

I'll compression test it in the next few days once I get a gauge from a friend. At least that will confirm or eliminate something.

As for the diaphragm allowing fuel to seep into the block, is there a way to check other than disassembly?

I did peek down into the cylinder when I had the spark plug out, and the piston does have a bit of black on it, but regardless a compression test will let me know if I burned out a ring.

And I removed the oil injection, so I'm running straight 1:128.

Thanks again, and I'll update this thread and not leave it hanging like I see most threads where people offer help, then never come back. :)

EDIT Stupid question, do I need to have the muffler installed for back pressure? Right now I have been testing without it and with just the exhaust pipe connected.

[saunteret]

OK, update...

Compression test is showing 25 PSI. Yep, twenty-five. Well, that could be part of my problem. Looks like a top end build is in my future. And might as well put in new seals while I'm at it.

[redcloud]

When you take the jug off and have the piston still on the rod take it and move it side to side parralel with the crank. If you get any rattle or loose movement, you will probably want to go right on with a long block re-build with new jug and the works. A bit more money but then you are done and fresh.
Probably not a pump issue with 25#'s compression.
The engine need back pressure but you should be able to start it and have some running of the engine for testing. With that low of compression the fuel can not compress and fire leaving the black.

[saunteret]

Thanks, redcloud. I am ordering my top end parts today, and there is a local golf cart company that I might call to have them pull the clutch/flywheel for me so I can have them press in the seals on the lower end since the engine will be pulled anyway.

And since the engine will be pulled, I plan on redoing all the electrical connections, fuel lines/filters and give the whole thing the once over.

Hopefully I'll have my cart back running soon.

[saunteret]

UPS said my parts will be here on Monday, so I decided to go ahead and pull the top end.

Here are some pics if anyone is interested.

[saunteret]

*deleted* Double post

[saunteret]

Just a quick thanks to redcloud and others that forged ahead before me... my cart is back up and running.



Dropped in the new top end rebuild kit, mixed up a new batch of 40:1 fuel, new Dayco drive belt and drove it around the farm for about 10 minutes at a low to medium RPM to break it all in.

Thanks to all, my cart is back running.