Valves stuck

[TrackPack]

I'm going through an original low mileage 383 with 906 heads. I have the heads torn down except for 3 intake valves that will not budge. Soaked with Aero Kroil, but no luck so far. Any ideas on how to get the valves out without destroying anything?

 

[JackR]

PB blaster and a heat lamp. They will loosen

 

[davek]

pb blaster works great,did you take off the clips and spring?

 

[TrackPack]

Yes, springs are removed. Seems like the stems are stuck in the guides. I'll try a heat lamp, although I did flash with a propane torch to warm up for penetrating oil.

 

[davek]

was the engine running when bought or was it sitting? PB the valves and let sit for a day. Then I would use a rubber hammer and gently tap them to see if they will move. If they move spray some move PB on them. Your guides might have to be replaced.

 

[69Bee]

The valves, guides, springs, and locks SHOULD be replaced. You have sprayed the valves, so keep knocking them back and forth, and spray with WD40, they will eventually loosen. If they are really stuck, get the valve head off of the seat and use the hammer and a punch on the head perifial to break it off. Then use a punch (or phillips screwdriver) to knock the stem out thru the top of the head. I do this often to get rusted or bent valves out. It is easier to break off the head and drive the stem up rather than continuing to try to drive it out thru the bottom. The valves are normally 2 piece units, and will break easily.

 

[TrackPack]

Numbers matching (71K original miles) engine sitting inside garage for about 30 years. Springs still had oil on them, surprised that they are stuck so tight.

No movement yet while lightly tapping with brass.

 

[TrackPack]

I forgot to mention, one valve stuck slightly open and two on the seat.

 

[BB BELLA]

you could try hot tanking and repeat,but your not going to reuse those valves so pound them out and get on with it!

 

[miller]

If you try to 'pound' those valves out, it's possible you will break the upper part of the valve guide.
906 heads on my 440, every valve was stuck, except a few. I wound up scrapping the heads, and replaced 'em.

Up to you, how far you want to go with things. Yes, the complete guides can be replaced, or sleeved if needed...probably.

 

[wyrmrider]

wd-40 is not the best tool for this job
KROIL or PB Blaster
heat
tap
could be bad gas varnish or rust so try a rust breaker

 

[Cranky]

My money is on old gas. Years back I let a car sit for too long without adding fresh gas or fuel conditioner. On one of my 'scheduled' runs, the float was stuck and it flooded the engine with that old gas. At that time, I didn't have the time to drain the tank and put fresh gas in it but a week later, I did but that was too late. That resulted in 2 stuck valves, two bent push rods, and a collapsed lifter......just after one week of letting that stale gas sit in the engine!

If your engine was last started with bad gas and the float was stuck, a running flooding engine, the valves will bounce gas up into the guides. Also, if you are pounding on the valve stems with a brass hammer or a drift, chances are good that you will flare the valve tips. Brass hammers and drifts are not as soft as most think and it's better to use a piece of aluminum instead. If you think the valve tips might be a little bit flared (they can also get that way from the rockers pounding on them), that a small grinder the bevel them before beating them through the guide. And I've never done what 69Bee said but yes, most factory valves are two piece units.

 

[wyrmrider]

what happened to me in my motorhome 440
ounce of prevention is worth a pound of cure
motorhome valves had two piece valves
exhausts had Inconel heads
intakes had SIL-xb stems
both were HARD CHROMED (not flash chromed after grinding)
work fine if you do not float the valves
you can break anything
hard chrome is a copper coat aschrome does not stick to steel
then nickel, then rough ground and chrome- finish grind
no easy way
I od hone valves to check for straight and bent valves and provide a better surface
some new valves are so bad they act like files
and they still stuck
I loosened the clearance on the rebuild and new springs- I'm running duals set tall

 

[69Bee]

My money is on old gas. Years back I let a car sit for too long without adding fresh gas or fuel conditioner. On one of my 'scheduled' runs, the float was stuck and it flooded the engine with that old gas. At that time, I didn't have the time to drain the tank and put fresh gas in it but a week later, I did but that was too late. That resulted in 2 stuck valves, two bent push rods, and a collapsed lifter......just after one week of letting that stale gas sit in the engine!

If your engine was last started with bad gas and the float was stuck, a running flooding engine, the valves will bounce gas up into the guides. Also, if you are pounding on the valve stems with a brass hammer or a drift, chances are good that you will flare the valve tips. Brass hammers and drifts are not as soft as most think and it's better to use a piece of aluminum instead. If you think the valve tips might be a little bit flared (they can also get that way from the rockers pounding on them), that a small grinder the bevel them before beating them through the guide. And I've never done what 69Bee said but yes, most factory valves are two piece units.

I do it often. When valves get bent, they usually won't go back far enough the remove the spring. Breaking off the valve head allows the stem to be removed easily. Also, valves that get bent also bend the stem up top. Forcing a valve with a bent stem above the guide can crack the top, especially with a thin top for positive seals. I just disassembled a Porsche head and had to break 6 out of 8 valves to get them out.

 

[PRHeads]

I use a cut-off wheel and cut the valve off even with the top of the guide.
Lots of PB Blaster and a good sized drift with a big hammer.
Sometimes despite being as careful as possible, the guide boss breaks off.
It’s not the end of the world.

 

[Fran Blacker]

I use a cut-off wheel and cut the valve off even with the top of the guide.
Lots of PB Blaster and a good sized drift with a big hammer.
Sometimes despite being as careful as possible, the guide boss breaks off.
It’s not the end of the world.

Was thinking same thing. But after cutting stems center punch and drill the stems some. Only question are the stems to hard to drill?

 

[Cranky]

I do it often. When valves get bent, they usually won't go back far enough the remove the spring. Breaking off the valve head allows the stem to be removed easily. Also, valves that get bent also bend the stem up top. Forcing a valve with a bent stem above the guide can crack the top, especially with a thin top for positive seals. I just disassembled a Porsche head and had to break 6 out of 8 valves to get them out.

How do you break the valve head off?

 

[TrackPack]

Well.....I managed to get one out. I filled the intake port with a 50/50 mix acetone and ATF for about 2 days. I then dumped most of the fluid out and with the port facing up I used a propane torch to heat the guide boss until fluid started to seep around the stem, then tapped it out. These intakes seem to be worn very little, and the stems are definitely stuck to the upper part of the guides.

Two to go.

 

[Ernie ingling]

Vice grip valve stem then with head secure to worktable apply rotation pressure to vc back and forth while smiting with a Ford wrench

 

[69Bee]

How do you break the valve head off?

Use a hammer and punch with the head off of the seat. The farther the better, but at least a quarter inch will work. Hit the valve head sharply on its peripheral, and it will break where the head and stem are friction welded.