Valve Guides

[D81938]

I have a question on my 217.8 flat head in my 38 D.B. The car sat in a barn for 40+ yrs.   Of course the valves were stuck.  After I got them all loose n observed the guides I'm kinda scared to remove the guides in the exhaust valves. They r rusted in there pretty bad. Should I let a machine shop remove them before I crack the block ?  Or should I heat in there n try to remove them with the threaded rod technique? Pulling them up out of the block.  Never worked on a flat head before. The motor has 49,861 original miles.. 3rd owner..   Thanks !! 

Edited February 6, 2022 by D81938

[Bryan]

10 hours ago, D81938 said:

I have a question on my 217.8 flat head in my 38 D.B. The car sat in a barn for 40+ yrs.   Of course the valves were stuck.  After I got them all loose n observed the guides I'm kinda scared to remove the guides in the exhaust valves. They r rusted in there pretty bad. Should I let a machine shop remove them before I crack the block ?  Or should I heat in there n try to remove them with the threaded rod technique? Pulling them up out of the block.  Never worked on a flat head before. The motor has 49,861 original miles.. 3rd owner..   Thanks !! 

I'm facing the same problem and have the same worry.  After removing bolts and having to drill out broke off ones, dealing with broke off oil galley plugs, etc that's the last thing to do, valve guides.  I bought an air hammer punch tool, planning on getting the Harbor Freight $14 air hammer and try it out with my brother's air compressor.   Biggest  worry is cracking the block.   Would suggest maybe clean the rust off with a wire brush or Dremel tool, then using penetrating oil.  A Map gas torch would probably help to heat around the guides.  If the valves and springs are out, I would drive them down from the top where the valves are.  How would one exert enough force to pull them up?  Don't think that would work.   If you have a 5lb hammer I would be very careful NOT to just beat like you're using a sledgehammer.  Might be better to use the air hammer.   

 

Valve guide - cut off and blend tops? - P15-D24 Forum - P15-D24.com and Pilot-house.com

 

https://p15-d24.com/topic/54231-help-me-further-understand-top-end-engine-wear/?do=findComment&comment=618110

 

[kencombs]

If dealing with a badly rusted guide, I think cutting off the upper part flush with the block prior to driving it down would be prudent.   A little 90 degree die grinder and cutoff wheel would make quick work of that. No point in taking a chance on it sticking.  And cutting off the offending part is much easier than trying to get all that rust off.

 

I've always driven the from the top, never tried to pull them.  A bolt small enough to replace the valve stem just doesn't look capable of the needed torque.

[rallyace]

If you are planning on having a machine shop do work on your motor, have them remove them. When I rebuilt my motor, I considered removing them myself and then thought that the machine shop would do a better job.  I had them remove the old ones, install the new ones and ream them to the correct diameter for the new valves.  One thing to pay attention to is that the guides for the exhaust valves go in 'upside down' compared to the intake valves.

[47 dodge 1.5 ton]

 Although you may want to wait for some of the experienced people to make a determination before moving forward on this motor. Your idea of tapping the hole very well may work.  I have removed many guides on some of my old tractors by tapping and using a slide puller with a threaded rod.

 

  I want to add— if you move forward with this path, make sure no chips end up in uncontrolled places. I guess my first thought, if the guides are that rusted, guessing you are doing a full rebuild?

Edited February 6, 2022 by 47 dodge 1.5 ton

[D81938]

That's the technique  thinking of using. Since my cam n tappets are still in engine.. thanks!! 

[47 dodge 1.5 ton]

Another option maybe worth a thought.  A shot of weld to the portion sticking above might be enough heat for removal. Do that a lot on bearing races at work with success(never tried on valve guides). Same with induction heater.

[Brent B3B]

I did the ones in my 1ton with the motor in the truck. 
https://m.youtube.com/watch?v=NVnDWdJrQBk&feature=youtu.be

if you drive them with the cam and tappets still in, you’ll need to break them off mid way. 
I used a vibrating saw to score them before I snapped them. 
and yeah, prep that baby like it is going into surgery ?

I plugged all the possible holes with towels, wrapped towels behind my work area and then I used tin foil to hold it in place.

 

oh yeah, I also bought a driver and setter

 

I was pleasantly surprised how much abuse that block took

Edited February 7, 2022 by Brent B3B
Spellcheck

[Bryan]

I saw that you mentioned wanting to pull them out but didn't know you weren't overhauling the entire engine.  Just assumed that.   First, how bad were the valves stuck in the guides?  If you only had to tap them out lightly maybe the guides aren't damaged.  Are the valve stems rusty?  How do the guides look inside?   How does the valve seats and  valve faces look?  Already had one person spend $1300 (too much) doing his valves and had other problems with his block. Be careful.   Need more info and maybe some pictures.

[Bryan]

 

[Sniper]

that $1300 claim is false, read the receipt, valve related machine work was $425 plus $150 in new valves.  The rest wasn't valve train related.

[Bryan]

33 minutes ago, Sniper said:

that $1300 claim is false, read the receipt, valve related machine work was $425 plus $150 in new valves.  The rest wasn't valve train related.

I just remembered him saying the $1300 and talking about valve work..wasn't trying to be misleading.   Main point is the poster is talking about doing valve work on a car he just got, and might not know of other problems that might be expensive.

[Sniper]

Sorry, the original poster of that receipt made the claim, which is what you are recalling, and is who I meant, not you.

 

Speaking of valve work, I can get the tools and parts to do my own guide work and valve job for less than the valve related machine work he was charged and I am not talking cheapo amazon off shore tools either.  Neway stuff.  Unless I need seats replaced. 

[Bryan]

On this I'm worried about what he was saying about it sitting so long now that I think of it.  He should probably be draining the oil, maybe pulling the pan to see how much gunk is in it.  Would be bad if we gave him all the valve advice, he gets that done, cranks it up with new high detergent oil in it and starts scraping bearings.  Hard to say without more info. Better advice might be clean the valve area up without pulling the guides, take pan off, clean it up and change oil (first non-detergent), put the head back on with a new gasket and get it running. If he bent a valve or chewed the face up getting them unstuck then maybe a new valve or two. If it doesn't knock and runs decent leave it be.  If it's knocking just do a complete overhaul.

[D81938]

Thanks everybody for all ur comments. Much appreciated!!  I'm gonna try something!!