99 ezgo eh29 295cc engine rebuild How far to go before I open it up?

[cedricbishop]

Just did compression tests on my barely running 99 eh29 Robin engine. Dry numbers were 55, 120PSI Wet 70, 160PSI. Looks like time for a rebuild. We have been adjusting the valves for a few months to get more pep out of her and this last time it was not enough to get up the hill. From the numbers and manuals on this site sounds like a full rebuild crank and cylinder head. I was looking for any helpful hints on any particular rebuild kits and well as the extent of a rebuild I am looking at. The inner lobe on my drivers side cam shaft shows some wear as well as the rocker. All the other lobes and rockers are smooth. Should I be looking at a new cam shaft? Or can this one be cleaned up? and does this offer any clue for this particular valve. When adjusting this valve in the past it was always a bit hard to get dialed in.

Looking around for rebuild kits.

Should I open it up and take measurements then buy?
Or is there a basic kit that I could upgrade to?
In this particular engine do you usually need new pistons or can you get by with a valve kit bearings and gaskets?

This cart is used for property maintenance and landscaping, lots of hills and at 2700' elevation.

Was also wondering if it might need to be re-bored. I noticed there are oversize pistons and rings available. Any comments?

[ez go go]

Let's go one by one, and hopefully someone will chime in to fill in the blanks I will leave.
First check out site sponsors for all your parts and rebuild kits. There are several to shop from easy to browse. Second, there is no way to know exactly where the problem lies so break it down like a single barrel. If your concerned about deep engine work, just take out the engine. Simple to do and less agravating than bending over or kneeling to work on the engine. I would pull the head and check the valves before I went to deep in the engine. These little engines are notorious for mushrooming the intake valve to the point it can't seal up to provide proper compression values. If you do have to tear into the bottom end the enigne specifications and tolerances in the repair manual will guide you in the process of cylinder boring. Using a mic will help you determine what the engine will need. Be aware that the cranks for these motors are pricey so hope that yours is fine. As far as the cam goes, I have refaced both the cam and the rockers with emery cloth and a buffing pad to get them smoothe and they worked out great. I'm not saying it's the right way, but it worked. You can buy rings or rings and pistons or a complete rebuild kit will everything. I generally buy just the needed items so I can save a buck and not have some stuff I don't need. On bottom end builds I replace all seals and pistons and rings. I only replace the pistons if the can looks to be scarred or scratched. I hope some of this answers your question and helps somehow.

[catsnw]

I rebuild my grandpa's cart and it really wasn't that bad. I bought a complete gasket kit and a crank seal. This and pistons/rings was all I needed to do a lower end rebuild. It have valve seals too. If you do the top you will need intake valves most likely. Get the head done by a pro(unless you know how to do valves) and get the block honed by a pro. Use the PDF of all the rebuild stuff be sure to have lots of paper to print the important stuff!! Also a ring compressor helps a ton and when you pull the drive clutch find a 3/4" fine thread bolt and a 5/8" wide rod. I picked the bolt off of a ford 8n front end.

Also use a bolt puller thing to remove the fan. I think it uses metric 6.5 or something like that.

[ez go go]

Cedric, if you do need to have the cylinder bored I would recomend taking it to a machine shop unless you are a machinist. I have a personal machinist that bores my engine block, refits crank rods and reassembles the lower end. This way he can turn the engine in the shop to make sure all is o.k.... As far as the valves, you can lap in the valves easily or for a few bucks more you can let the shop do it and your done.

[BLUE72CAMARO]

If you havent started looking at prices for rebuilding one of these little engines prepare to be shocked! There is nothing cheap about rebuilding one of these little motors.

[cedricbishop]

Thanks for all the information. I am about to start out in the garage. I am sure I will run into questions soon. Thanks
Cedric