Engine repair or swap to LDS?

[DaneGer21]

Maybe we can get a group buy from BM to lower the price a bit?

(6) rockers and (2) gaskets came to $314.40

 

[Computerdoc08]

What PN do you have for the rocker arms?

 

[davidb56]

Im sure you all know there is some guidelines when swapping rockers, and what to expect, but here is a interesting article on rocker ratios, valve spring compression and piston clearance, plus cam lift and duration. https://www.chevyhardcore.com/news/can-you-gain-horsepower-by-changing-rocker-arms/

 

[DaneGer21]

What PN do you have for the rocker arms?

Part# 11641735

 

[rustystud]

Since the exhaust is clean would you recommend only replacing the intake guides? Intake valve stems are close to the limit so I was planning on reusing them. I don't have a .0001 mic so not certain how close. Bad idea?

If your valves are worn, just replace them. Since your removing the heads anyway, just have the machine shop check the valve guides. They might be fine and the seals are just bad. Since the seals are not much on the deuce, I would have the machine shop "machine" the top of the guides to except a modern oil seal. The modern seals will last decades under daily use.
If the guides are a bit worn they can just "knurl" them. They will last a long time after that procedure.

 

[ldmack3]

Took a close look and the guides have been knurled. Engine was depot overhauled in 1987.
The seals I've seen fit inside the springs, either floating or fixed. Didn't see either one. Don't see any in the IPC either.
Valve stems are right at the limit, so I'll get the shop to check it all out. They go in Monday, will take 2 weeks they said.

 

[davidb56]

If your valves are worn, just replace them. Since your removing the heads anyway, just have the machine shop check the valve guides. They might be fine and the seals are just bad. Since the seals are not much on the deuce, I would have the machine shop "machine" the top of the guides to except a modern oil seal. The modern seals will last decades under daily use.
If the guides are a bit worn they can just "knurl" them. They will last a long time after that procedure.

I didnt see any reference in my manual on valve guide seals. that doesnt mean they couldn't be added though, if he cant get new valve guide inserts. Am I missing it somewhere?

 

[ldmack3]

Can they be added with those valve rotor things in there?
If I end up having to replace guides and valves, I won't mess with adding seals. Otherwise, it will depend on the cost for P&L.

 

[rustystud]

I didnt see any reference in my manual on valve guide seals. that doesnt mean they couldn't be added though, if he cant get new valve guide inserts. Am I missing it somewhere?

The ones I have seen where just "O" rings riding on the valve stem.

 

[rustystud]

Can they be added with those valve rotor things in there?
If I end up having to replace guides and valves, I won't mess with adding seals. Otherwise, it will depend on the cost for P&L.

The machine shop should be able to machine down the guide to except the valve seal. It should clear the springs just fine. There pretty small.

 

[Gypsyman]

Any chance that adding seals where none were intended to be could cause the stems to run "dry" and accelerate wear? Something to consider.

 

[V8srfun]

Any chance that adding seals where none were intended to be could cause the stems to run "dry" and accelerate wear? Something to consider.

usually valve guides are a brass alloy that is considered to be self lubricating. At least that is the way I understood it.

 

[Gypsyman]

usually valve guides are a brass alloy that is considered to be self lubricating. At least that is the way I understood it.

Agreed, but some years back we added valve stem seals to an old tractor engine during a rebuild at the owners request. Less than 50 hours late the guides were shot and the tractor was smoking. Went back in and did the guides again but without stem seals this time. That tractor is still running smoke free some 20+ years later. That experience always pops up in the back of my aging mind when dealing with older engines/technology.

Not right or wrong. Just something from past experience.

 

[V8srfun]

Agreed, but some years back we added valve stem seals to an old tractor engine during a rebuild at the owners request. Less than 50 hours late the guides were shot and the tractor was smoking. Went back in and did the guides again but without stem seals this time. That tractor is still running smoke free some 20+ years later. That experience always pops up in the back of my aging mind when dealing with older engines/technology.

Not right or wrong. Just something from past experience.

No argument there. One could also look at it from the prospective that if it doesn’t smoke without the extra seal then why add it. But that is interesting though I would never have thought that adding valve seals would ever cause excessive wear. That is one of those things that you would never know until you tried.

 

[ldmack3]

Good points. Has anyone here successfully added seals to a multi fuel?

 

[gringeltaube]

Has anyone here successfully added seals to a multi fuel?

We never heard of it - and probably never will...

Really, for me that would be the absolute last thing to do, from a long list of possible improvements for these engines. At the top of my list is correct balancing of all internals! (before someone asks...)

 

[ldmack3]

We never heard of it - and probably never will...

Really, for me that would be the absolute last thing to do, from a long list of possible improvements for these engines. At the top of my list is correct balancing of all internals! (before someone asks...)

I've got considerable oil leaking through the valve guides. So I may have to choose replacing all guides and valves while the heads are off being worked or I was thinking valve guide seals might be a way to go. But sounds like not a good idea.

 

[Mullaney]

I've got considerable oil leaking through the valve guides. So I may have to choose replacing all guides and valves while the heads are off being worked or I was thinking valve guide seals might be a way to go. But sounds like not a good idea.

.
Could be an inexpensive short term valve guide fix.

Thinking about small block Chevrolet heads that had "umbrella seals" inside the valve springs on the stock version of those cars. Primary job that they did was to keep the splash of oil from running down the valve stems - causing the oil talked about earlier.
Not sure what kind of life expectancy they had...

 

[rustystud]

There are several factors you need to consider before discounting using valve seals. One, the military didn't use them as the life expectancy for the deuce was considered in weeks not years. Let's face it, the Deuce was a "throw-away" truck. Anyone can see this by the "Spartan" way it was built. No creature comforts at all. Even the heater was only used for "artic" conditions. So why spend money on an engine that in all likelihood will be blown to bits in short order ?
Second, yes the incorrect valve guide seal can cause problems with the valve stem by drying it out causing extreme wear. The Chevrolet engines "Umbrella" seals was mentioned. They were a basic seal which barely kept out the oil. It still allowed plenty of oil by to lubricate the stems. This type of seal would not hurt the MultiFuel engine at all.
Thirdly, oil pressure is a major factor. In the aforementioned Chevy engines, they have very little oil pressure in the rocker/valve train area, 5 to 10 PSI is very common. So not much was needed to keep oil out of the guides. The Deuce on the other hand can have up to 30 PSI of pressure up there, and sometimes more at highway speeds (2200 to 2400 RPM) . I've put a pressure gauge up there and recorded pressures of up to 40PSI in the rocker rail.
That's a lot of oil slinging around. That is why you see valves with caked on oil.
So if you don't drive on the Highway/Freeway much, I wouldn't worry about adding seals to the valve guides. Now if you do spend some quality time over 40 MPH, I would consider looking into adding some seals to the guides. The amount of oil you will save besides the amount of pollution you will stop causing will be considerable. Remember "rolling coal" is not a good thing.

Now someone might look up my past posts on this topic. Yes, in the past I have been an advocate of keeping the valve guides free of seals. It does increase lubrication of the valve stems. I've also never driven much on the Highway/Freeways . I keep to the side roads pretty much. So I don't have much of an oil buildup on my valves. So it pretty much comes down to how you drive your Deuce.

 

[ldmack3]

Heads are at the shop and it will be 2 weeks before they can work them. If they say I need to replace valves and guides, I won't do the seals. If they say they are ok, I'll discuss with them.
Thanks all.