[scuba14c]

I have leaky piston rings on my 1983 VF750F Interceptor. I looked on mrcycle.com for the replacements and found several different types. Which ones should I get to replace the damaged stock rings?

[Quick 26]

have you pulled it apart yet?

[scuba14c]

No, I am trying to get to that in the next week or so. Does it matter if it is apart?

[sinfuldragon]

I think his theory is to take it apart first to be sure thats your issue... but I've been wrong before

[Quick 26]

how do you know your rings are bad? did you do a leak down test? does it smoke all the time or just when its cold? did you do a compression test?

[Quick 26]

also, you ask which ringset to get, what are the options? if it were me, and i were that far into it i would prob replace the pistons. depending on what sleve you have you may need to get it machined or re-coated

[scuba14c]

I did a compressiion test on it. The engine has not started since I have had it. Compression was down to 60psi in a cylinder when it was cold. After I dumped a little oil into the cylinder, compression went up to 190psi.

As for replacing the pistons, I don't have a lot of money to sink into this project, I'm in college. Why would the sleve be bad?

Also, the problem that made me tear this engine apart was a coolant leak into the crankcase. Would bad rings be a feasible cause for this?

[sinfuldragon]

I would be thinking more along the lines of a bad head gasket

[Quick 26]

head gasket, cracked head or cracked sleave can cause coolant leaks along with a bad water pump seal. you will have to look at the pistons once you get it apart and see how they look. they are a "wear" item. as far as the cylinders, i am not sure how they did that year bike, if its nickle sealed or if its steel. if its steel you can just hone it if its not all scarred up, if its sealed you have to have it replated it its screwed up. you will know right away if its sealed and screwed up. if you are not too worried about the bike i say call honda order a new set of replacement rings and let it roll, but make sure you find your coolant leak first. if you can find a radiator testor get someone to pressurize your system and see if you can find the leak

[zfrilly2]

190 p.s.i. is pretty good actually high. doesn't sound like the rings ar bad.

[Quick 26]

he said it was that high after he squirted oil in the cylinder

[zfrilly2]

The engine had been sitting awhile. It is a good idea to do this, normaly atf is alittle better than oil for this. The compression will drop back down a little, but it is a good way to "unstick" the rings a little after prolonged sitting.

[scuba14c]

I've got the top end disassembled, and the gaskets look ok. When I pulled it apart, there was a pool of coolant sitting in cylinder 2. I'll update with more info when I rip the bottom apart.

[Quick 26]

9 times out of 10 you will get coolant in the cylinder when you pull the head off

[scuba14c]

I've run into a small problem, but found the leak. One of the coolant openings in the head gasket was torn on cylinder 2, which also has bad rings. That problem is taken care of. However, to get to pthe pistons, I need to get into the crankcase. Wat is a puller and how does it work (for taking off the alternator)? Do I even need one? I can rent a 9" pulley puller at a local hardware store, will this work?

[zfrilly2]

The puller threads into the flywheel and has a screw inside it that press against the crankshaft to remove th flywheel (usually). A regulr 9in puller will not work, it will damage your flywheel. The pullers are cheap and very universal, check the pructs it works on when buying. They are normally around $15-$25. Many motorcycle shops have them and since they are universal (somewhat) check other mannufactures to find them locally.

[Quick 26]

seems like the cylenders should slide off without having to split the cases. and if you get a puller get the CORRECT one.

[scuba14c]

The cylinders are an integral part of the case. The clymer manual says to access the pistons, I need to partially disassemble the lower end. But if you have any shortcuts, I'd be glad to hear them.

[Quick 26]

on that bike i think the cases have a horizontal split instead of a vertical dont they? if its a vertical split, you are going to have quite a bit of dissasembly

[scuba14c]

It's a horizontal split. I can't find a bike dealer locally that has a rotor puller. Can you point me in the right direction online?

[Quick 26]

try denniskirk.com

i am suprise the jugs dont come off. why do you need to pull the flywheel if its a horizontal split

[zfrilly2]

I'm with Quick. Probably don't need to pull the flywheel if it splits where the crankshaft runs.

[zfrilly2]

If you found the problem up top why split it, the compression seems ok. Are the cylinders scored?

[scuba14c]

No, the cylinders look ok, but the compression on 2 cylinders is below 100psi.

I found these pullers

KOWA - 2000: Flywheel & Rotor Puller

Motion Pro - 08-0074 - Flywheel Puller (M22 x 1.5 RH)

The second one seems to be a little simple for what I am doing. Which one will work?

[Quick 26]

i have some of the motion pro ones, just remember snug it and wack it with a hammer. if it dont pop snug it again wack it again

[zfrilly2]

motio pro makes great tools. use a little pb blaster to help ease it off.

[scuba14c]

So, how exactly does this little tool work? I really don't see how a small screw will help me?

[Quick 26]

take the flywheel nut off then you screw the too in the flywheel until you get pressure on it and easily trun it in untill it pops the flywheel off. when you get it tight you should hit it with a hammer to jar it loose

[scuba14c]

Ok, sounds pretty easy. I ordered it a couple days ago, so the engine should be apart by next week. I'm having a little trouble with the coolant pump though. I got the outer cover off, but I can't get the impeller and case off the engine. I should just be pulling straight back, right?

[zfrilly2]

Have to check a manual on that, as I have never worked on that particular engine.