Anyone know anything about OHC motors?

[notfred]

Specifically, I want to know if you can replace valve guide seals on a 1.5 liter SOHC Honda motor (86 CRX) w/o pulling the head off the block.

Anyone have any idea?

 

[white]

not that i've ever done this before, but i think you can do it as long as you don't drop the valve into the cylinder. i'm not sure how you'd do that though. i looked in my honda service manual for an 85 CRX and they did it by removing the head.

 

[yakko]

If the valve set up is anything like my VWs then yes you can. On my car you take out the spark plugs and then pull off the valve cover and then the cam. You then need to remove the lifters. To get the vavle up you will need to have an air hose connected to a fitting that goes into the spark plug hole. This closes the valve and allows access to the seal.

 

[PsychoAndy]

bump for mechanics that can help notfred

-PAB

 

[Evadman]

Originally posted by: yakko
If the valve set up is anything like my VWs then yes you can. On my car you take out the spark plugs and then pull off the valve cover and then the cam. You then need to remove the lifters. To get the vavle up you will need to have an air hose connected to a fitting that goes into the spark plug hole. This closes the valve and allows access to the seal.

Or you can do it the way I did and just stuff the champer with a bunch of rope coiled in though the spark plug hole.

 

[Balthazar]

Originally posted by: Evadman

Originally posted by: yakko
If the valve set up is anything like my VWs then yes you can. On my car you take out the spark plugs and then pull off the valve cover and then the cam. You then need to remove the lifters. To get the vavle up you will need to have an air hose connected to a fitting that goes into the spark plug hole. This closes the valve and allows access to the seal.

Or you can do it the way I did and just stuff the champer with a bunch of rope coiled in though the spark plug hole.

Yeah, lets not do that shall we....

 

[Bluefront]

I've done it several times using the compressed air method described above. You get both valves on that cylinder closed (or all four if that's the case) ....compression stroke. Then you compress the air in that cylinder using a special adaptor and a powerfull compressor. You still need a special tool of some sort to depress the spring.

With valve sizes being so small these days....this type of job is very difficult. I wouldn't recommend anyone to try it in his driveway. The odds of screwing up are pretty good.

Probably would be easier to bite the bullet...pull the head. Wouldn't take much more time....

 

[Slacker]

I wouldn't recommend anyone to try it in his driveway. The odds of screwing up are pretty good.

Hehehe, I dropped a valve inside the cylinder of engine I was working on in my driveway, there was no way I was going to tear the motor down to get it back, I took off the exhaust manifold and put a finger in there and wiggled it around until I got the valve to stand up on the piston and carefully rotated the engine by hand to raise the piston until the valve was close to the guide, then I lined it up and rotated the engine by millimeters until the valve started up the guide, it took about an hour of sweating and cursing but I got it back

At that time I didnt know enough about engines to know that it could have started while being rotated by hand, if that had happened I fould have lost a finger ?^?

 

[yakko]

Originally posted by: Bluefront
You still need a special tool of some sort to depress the spring.

Dammit! I knew I was forgetting some part of it.

 

[CraigRT]

I would pull the head off, and just make it easier, pick-up a new head gasket and make sure the car is all mint when you put it back together, do it the right way if you can.. i think you should pull off the head.. but that's just me.. it's alot of work, but it could pay you back in the long run..

 

[yakko]

Originally posted by: Yield
I would pull the head off, and just make it easier, pick-up a new head gasket and make sure the car is all mint when you put it back together, do it the right way if you can.. i think you should pull off the head.. but that's just me.. it's alot of work, but it could pay you back in the long run..

Pulling off the head does not make it easier. They make valve spring depressors because they know that taking the head off is neither easier or necessary.