Split Valve Guide Installation Advice wanted

[SoCal_Alden]

I've removed the head on my 29CCPU as it was leaking coolant into the exhaust and had it hot tanked, magnafluxed and milled.

While at it decided to lap the valves and replace the split guides.

What is your preferred method for intalling the split valve guides?

Any info is greatly appreciated.

[James Rogers]

Myself, I install them into a garbage can. I have only ever replaced 1 set long, long ago. With the price of a new set of modern valves and guides, I will never install another stock set.
I hope you kept the guides in pairs? If you didn't you will have to replace them with new anyway. Might as well make it an upgrade and use modern.

[SoCal_Alden]

Thanks James,

The valves are in good shape, but the engine had not been taken care of (oil changes) when I got it and thus only want to replace the guides at this point in time.

Just don't know the best way to get the new split guied up into their proper position.

[RHD]

Good advise. I would never go back to 2 pce valve guides.

[pat in Santa Cruz]

They should just push in place. Drop the valve in the bore, place the guides around the valve stem and push up. If they do not fit, possibly the bores are dirty. Unless they are exactly the same centers as the old ones, I would think the seats now must be re-surfaced to be concentric with the new guides.. I always end up having modern guides and valves put in. They're good quality American valves. If the original guides are so worn, the stems probably are too...might as well do the whole job the right way and be done with it. Its too much work to have to repeat it any time soon.

[Glenn C.]

Sponsored Links (Register now to hide all advertisements)

Some of the repo guides that were made in Argentiena a few years back, were finish machined too large on the outside diameter of the guide flange to set down into the recess of the block. This required machining of about .015" from the O.D. of the guide flanges. Take the advice of the other posts, and install modern one piece guides and modern valves.

[SoCal_Alden]

Sigh,

I've invested $ into the split guides (recent purchase from Snyders) and will try to fit them into the bore this coming week.

I'll keep everyone posted on the outcome.

Thanks for your suggestions.

[James Rogers]

Originally Posted by SoCal_Alden

Sigh,

I've invested $ into the split guides (recent purchase from Snyders) and will try to fit them into the bore this coming week.

I'll keep everyone posted on the outcome.

Thanks for your suggestions.

Now see, you didn't say you were using new guides! This means the whole process you have started is to be done again and with more work to be correct. You will need to insert the guide into the bore by itself and ream it to fit the valve stem. Are the valves new? This is where at least half of the wear is in the train.Next, the valves will have to be put in with the guide in place and the valves lapped in place to insure the seat is concentric and the valve contacts all the way around and in the middle of the valve seat. You talk about lapping the valves and replacing the guides with lapping in the context of being the first process. This won't work. The valves have to be lapped, in place, with the guide it will run in and in the pocket it will stay in. A good, properly done valve job will make or brake the smoothness of the way the engine runs. I believe, many times, the problems with the erratic running can be attributed to leaky valves and cause many other systems to be blamed for this problem when adjusting these systems does not cure the problem.

[George Miller]

Originally Posted by James Rogers

Now see, you didn't say you were using new guides! This means the whole process you have started is to be done again and with more work to be correct. You will need to insert the guide into the bore by itself and ream it to fit the valve stem. Are the valves new? This is where at least half of the wear is in the train.Next, the valves will have to be put in with the guide in place and the valves lapped in place to insure the seat is concentric and the valve contacts all the way around and in the middle of the valve seat. You talk about lapping the valves and replacing the guides with lapping in the context of being the first process. This won't work. The valves have to be lapped, in place, with the guide it will run in and in the pocket it will stay in. A good, properly done valve job will make or brake the smoothness of the way the engine runs. I believe, many times, the problems with the erratic running can be attributed to leaky valves and cause many other systems to be blamed for this problem when adjusting these systems does not cure the problem.

JAMES GIVES GOOD ADVICE
Along with what he said you also need to keep the guide in the exact same spot in the bore of the block. The bore in the two piece guides are not always concentric with the OD.
With all that said you would be better off leaving them along or doing it right, by grinding the valves and seats. If you get it done by lapping you are going to wind up with way to wide of seats. Wide seats are not good.

[SoCal_Alden]

Thanks for everyone's suggestions. Turns out the valve-guide bores were crudded up - cleaning them out with a manual wire brush did the trick. Installed the new guides with some Lubriplate and the rest went back to gether without further incident.


The head was another matter - seems the hot-tanking cleaned out a hole between the water jacket and the distributor hole - didn't notice until after - sigh - I had it all back together and fired up.

Then took everything apart (easier the second time around though), flushed the oil pan and procured another head. Finished up yesterday evening and this afternoon went around the neighborhood - Great to be back on the road again!

Thanks again to everyone's advice.

Cheers !!!

Originally Posted by SoCal_Alden

I've removed the head on my 29CCPU as it was leaking coolant into the exhaust and had it hot tanked, magnafluxed and milled.

While at it decided to lap the valves and replace the split guides.

What is your preferred method for intalling the split valve guides?

Any info is greatly appreciated.