91 L98 Head Stuck
Instructor
Joined: Apr 2013
Posts: 144
Likes: 0
From: NW Arkansas - usually winter in FL
LOL - - yup you have to use grease - and yes it does take a bit - but it works. Used to buy grease in a five gallon pail, guess it didn't seem like a lot then -
Guess you could use oil instead - if you could discover a way to pressurize the cylinder with it.
Anyway, good luck
Jake
Guess you could use oil instead - if you could discover a way to pressurize the cylinder with it.
Anyway, good luck
Jake
Last edited by jake corvette; Sep 11, 2014 at 04:55 PM.
Thread Starter
Instructor
Joined: Apr 2013
Posts: 152
Likes: 0
I set the engine in the floor, put starter, etc... back on and tried cranking it over. That didn't work. The rockers and push rods are off so valve were closed the whole time. I installed all four plugs on that side. Could that maybe affect this method in some way.
If I can rig something up for the compressor I'll try that next. I don't have one of the rubber nosed air guns but I can pick one of those up on the way home tonight. Does anyone know right off what thread the plugs are? I should know this but... Wait, I have fittings with my compression gauge, hmmm. evrything would be backward but maybe I could use that as a base.
We use grease at work to remove stubborn bearings and couplings. It usually takes some rigging but that is a good option should all else fail.
Thanks again
If I can rig something up for the compressor I'll try that next. I don't have one of the rubber nosed air guns but I can pick one of those up on the way home tonight. Does anyone know right off what thread the plugs are? I should know this but... Wait, I have fittings with my compression gauge, hmmm. evrything would be backward but maybe I could use that as a base.
We use grease at work to remove stubborn bearings and couplings. It usually takes some rigging but that is a good option should all else fail.
Thanks again
Melting Slicks
Joined: Jun 2013
Posts: 3,065
Likes: 39
I set the engine in the floor, put starter, etc... back on and tried cranking it over. That didn't work. The rockers and push rods are off so valve were closed the whole time. I installed all four plugs on that side. Could that maybe affect this method in some way.
If I can rig something up for the compressor I'll try that next. I don't have one of the rubber nosed air guns but I can pick one of those up on the way home tonight. Does anyone know right off what thread the plugs are? I should know this but... Wait, I have fittings with my compression gauge, hmmm. evrything would be backward but maybe I could use that as a base.
We use grease at work to remove stubborn bearings and couplings. It usually takes some rigging but that is a good option should all else fail.
Thanks again
If I can rig something up for the compressor I'll try that next. I don't have one of the rubber nosed air guns but I can pick one of those up on the way home tonight. Does anyone know right off what thread the plugs are? I should know this but... Wait, I have fittings with my compression gauge, hmmm. evrything would be backward but maybe I could use that as a base.
We use grease at work to remove stubborn bearings and couplings. It usually takes some rigging but that is a good option should all else fail.
Thanks again
Race Director
Joined: Apr 2003
Posts: 17,700
Likes: 1,667
From: moraga ca
Take a strong gasket scraper or quality putty knife or large bladed sharp screwdriver. Where the head meets the block in the corner of the valley near the china wall, place one of these tools in the gasket space and hit the end with a hammer or mallet. The head will break loose. It may scuff the head a little, but it is in a non sealing area and won't affect the head sealing. Been there, done that.
Instructor
Joined: Apr 2013
Posts: 144
Likes: 0
From: NW Arkansas - usually winter in FL
The older "normal" sized sparkplugs have 14 millimeter threads - not sure what the newer smaller plugs might be -
Quite simple to make an adapter - just use an old spark plug shell and weld/braze the appropriate connector to it. Might even be able to tap the inner part of the metal sparkplug shell itself and then simply screw your adapter into it.
Just some thoughts –
Jake -
Quite simple to make an adapter - just use an old spark plug shell and weld/braze the appropriate connector to it. Might even be able to tap the inner part of the metal sparkplug shell itself and then simply screw your adapter into it.
Just some thoughts –
Jake -
Melting Slicks
Joined: Nov 2005
Posts: 2,736
Likes: 0
From: WAY UPSTATE NY
Take a strong gasket scraper or quality putty knife or large bladed sharp screwdriver. Where the head meets the block in the corner of the valley near the china wall, place one of these tools in the gasket space and hit the end with a hammer or mallet. The head will break loose. It may scuff the head a little, but it is in a non sealing area and won't affect the head sealing. Been there, done that.
..This..or you really don't have all the bolts out..
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Melting Slicks
Joined: Jun 2013
Posts: 3,065
Likes: 39
Melting Slicks
Joined: Jan 2008
Posts: 2,054
Likes: 120
From: AZ
Rather than the rubber tipped, I'd use a screw in, like some of the better compression testers employ.
The best penetrating oil is a mix of acetone and ATF; 50:50, I think. The tough part is getting it in where the real adhesion lies.
Any chance this engine was in a flood? My other thought is possible nasty damage to the head from the chemical weld from the dissimilar metals and some water.
Hope not!
The best penetrating oil is a mix of acetone and ATF; 50:50, I think. The tough part is getting it in where the real adhesion lies.
Any chance this engine was in a flood? My other thought is possible nasty damage to the head from the chemical weld from the dissimilar metals and some water.
Hope not!
Last edited by whalepirot; Sep 14, 2014 at 12:10 AM.
Burning Brakes
Joined: Mar 2013
Posts: 1,131
Likes: 5
From: Illinois/Wisconsin Line
Here is something I found on another site with the same problem.
if the motor isnt stuck and you can get a starter hooked up to it, pll the spark plugs on the bank you want to remove, thread some rope (cotton clothes line works good,) into the spark plug holes and bump the motor over with the starter, when the piston comes up, the rope will push the head off.
Sure you got ALL the bolts? Manifold is off, right? Can you take a piece of steel about 2 foot long with a right angle on the end and bolt this to something on head so you can put a little muscle to rock the head back and forth? Leverage?
caleb, take a wooden hammer handle and stick into one of the ports and then pull the handle at the other end then if it is still stuck use a rubber mallet or dead blow hammer to hit the head while pulling if still no good and now that I think about it just put something in the valley and use a long handle in the port and use the thing in the valley as a fulcrum (pivot point) so you will have enough leverage to pry it off
Caleb, you still have bolts in there somewhere!
if a hammer handle in an intake port won't pop it, you still have it bolted on!
if the motor isnt stuck and you can get a starter hooked up to it, pll the spark plugs on the bank you want to remove, thread some rope (cotton clothes line works good,) into the spark plug holes and bump the motor over with the starter, when the piston comes up, the rope will push the head off.
Sure you got ALL the bolts? Manifold is off, right? Can you take a piece of steel about 2 foot long with a right angle on the end and bolt this to something on head so you can put a little muscle to rock the head back and forth? Leverage?
caleb, take a wooden hammer handle and stick into one of the ports and then pull the handle at the other end then if it is still stuck use a rubber mallet or dead blow hammer to hit the head while pulling if still no good and now that I think about it just put something in the valley and use a long handle in the port and use the thing in the valley as a fulcrum (pivot point) so you will have enough leverage to pry it off
Caleb, you still have bolts in there somewhere!
if a hammer handle in an intake port won't pop it, you still have it bolted on!
Burning Brakes
Joined: Mar 2013
Posts: 1,131
Likes: 5
From: Illinois/Wisconsin Line
First, locate cylinders with both valves closed. Then, make up a fitting with an old spark plug and a zerk fitting (actually, you'd need several). Pump the cylinder full of grease and then keep pumping. The hydraulic pressure will raise the head enough to get wedges under it. I haven't tried this myself but I've talked to a couple of people who have used it satisfactorily.
Burning Brakes
Joined: Mar 2013
Posts: 1,131
Likes: 5
From: Illinois/Wisconsin Line
This guy made and plate and used a puller. Worked for him
http://www.fordbarn.com/forum/showth...0063&showall=1
http://www.fordbarn.com/forum/showth...0063&showall=1
Safety Car
Joined: Sep 2004
Posts: 3,953
Likes: 550
From: Mission Viejo CA
Boy, this has sure collected a huge number of suggestions! There must be cooling system corrosion to cause this much trouble! Here's another idea:
Leave the rockers off. Put the front cylinder (is it #1 or #2?) at TDC.
Fill the combustion chamber with heavy oil. Rotate the crank a little. Pour in a little more oil, maybe 40-50cc. Install a spark plug. Repeat this oil injection process in the rear cylinder. Install a spark plug. Remove the center two spark plugs. Hit the starter!
Leave the rockers off. Put the front cylinder (is it #1 or #2?) at TDC.
Fill the combustion chamber with heavy oil. Rotate the crank a little. Pour in a little more oil, maybe 40-50cc. Install a spark plug. Repeat this oil injection process in the rear cylinder. Install a spark plug. Remove the center two spark plugs. Hit the starter!
Melting Slicks
Joined: Jun 2013
Posts: 3,065
Likes: 39
I have another idea. Do you have an engine hoist? If you do, you can put 1 bolt in the front accessory bolt hole of the head, and 1 bolt in the rear of the head with a chain and hook the chain the hook on the engine hoist and pump it up.
Burning Brakes
Joined: Mar 2013
Posts: 1,131
Likes: 5
From: Illinois/Wisconsin Line
If you live near a Foundry. Bring ur motor by and ask if you can put it in one of their Huge ovens. My buddies have one thats like 24x24 with railroad tracks going into it, and for the stuff that calls for Hardening. It goes in the oven, sometimes thousands of parts at once. At 350 degrees of so for 24 hrs. To give the metal a hardness of the top .004 or so of the stuff surface. Rockwell Hardness
Put your motor in one of those and set for 200 degrees after 12 hrs or so, it will pop right off, warmed.
Put your motor in one of those and set for 200 degrees after 12 hrs or so, it will pop right off, warmed.
Thread Starter
Instructor
Joined: Apr 2013
Posts: 152
Likes: 0
Take a strong gasket scraper or quality putty knife or large bladed sharp screwdriver. Where the head meets the block in the corner of the valley near the china wall, place one of these tools in the gasket space and hit the end with a hammer or mallet. The head will break loose. It may scuff the head a little, but it is in a non sealing area and won't affect the head sealing. Been there, done that.
Finally decided to go for broke and took the stiffest putty knife I had and tapped it in as suggested above. Then went to small flat head screw driver then a larger one until it came loose. Head number two took all of about 15 minutes to remove. The head gasket is an orange color and just about disintegrated.
Thanks for all the suggestions, I learned slot.