Replacing valve cover gaskets
Moderator: alh
Replacing valve cover gaskets
One of the valve covers on my 1967 Dino spider is leaking some oil onto the spark plugs. I ordered some new gaskets from Dinoparts and was going to do the install myself. Are there any tips or things to be aware of when replacing the gaskets? Looks like I need to remove a bunch of parts (air box, hoses, throttle linkage, etc) to remove the valve covers.
Thanks
Dennis
Thanks
Dennis
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- Dino: Fiat Dino 2.0 Spider
- Location: NE Washington, USA
Re: Replacing valve cover gaskets
Hi Dennis,
This is a simple job, but because of the shape of the cover you
Must follow some rules.( others jump in if I miss something)
First removal, go slowly and take pics. Not the location of the hoses and fittings on the u/s of the airbox. From you comment I assume you doing the distributor side as you don’t need to do anything with the throttle linkages on the other side.
Just be careful remove the throttle shafts, don’t let any parts going flying as some are spring loaded. Just take lots of pics and take your time.
Remove the cam shaft end caps ( note where each cap came from)
Do not remove the distributor until you mark the location of each pice relative to the covers. Do not rotate the engine just incase you get past 180 deg. ( it’s just a hastle timing again)
Remove the cover carefully. It may be stuck down with over zealous amount of sealant.
When it’s all apart, it’s cleanup time.
If you’re lucky there is no gasket or sealant stuck to the head, if there is you must not scrape anything off until you spend a lot of time stuffing proper towels all around the cams and cam buckets. Do not use paper towel. The goal is to keep all the crap outside the engine.
Use a proper gasket removal scraper. They have the right angle without being sharp enough to scratch either the alloy head or the very soft magnesium cover.
For stubborn sealant there are some chemical softeners you can use. Don’t use sand paper, you can’t contain the grit or keep a level surface.
Both surfaces must be totally clean.
Pay a lot of attention to the end covers.
When you are convinced you have everything removed, pre fit the gasket so that you know which way they fit. I kept the spacer stops in place until I knew exactly which way they fit up. Infact I didn’t cut them until the last minute.
Buy a superior sealant, I only ever use Yamabond since Honda stopped selling theirs.
I have used this for years on cars and even old Brit bikes that are designed to leak oil.
Apply a thin even coat to either the gasket ( simpler) or the metal, not both. Assemble as quickly as possible, use a short metal straight edge like an engineers SS 150mm rule to ensure the end cap area is flush ( this is a Leakey area, use a torque wrench, you will over tighten these small bolts without one.
Leave over night, recheck the torque before doing the end caps. Same procedure, not too much sealant, theoretically the gasket is sufficient, but with old castings and engines they need a little help.
PS start tightening the covers from the middle out.
Put it all back together, let it sit for a few hours before starting up.
Just take your time.
Michael
This is a simple job, but because of the shape of the cover you
Must follow some rules.( others jump in if I miss something)
First removal, go slowly and take pics. Not the location of the hoses and fittings on the u/s of the airbox. From you comment I assume you doing the distributor side as you don’t need to do anything with the throttle linkages on the other side.
Just be careful remove the throttle shafts, don’t let any parts going flying as some are spring loaded. Just take lots of pics and take your time.
Remove the cam shaft end caps ( note where each cap came from)
Do not remove the distributor until you mark the location of each pice relative to the covers. Do not rotate the engine just incase you get past 180 deg. ( it’s just a hastle timing again)
Remove the cover carefully. It may be stuck down with over zealous amount of sealant.
When it’s all apart, it’s cleanup time.
If you’re lucky there is no gasket or sealant stuck to the head, if there is you must not scrape anything off until you spend a lot of time stuffing proper towels all around the cams and cam buckets. Do not use paper towel. The goal is to keep all the crap outside the engine.
Use a proper gasket removal scraper. They have the right angle without being sharp enough to scratch either the alloy head or the very soft magnesium cover.
For stubborn sealant there are some chemical softeners you can use. Don’t use sand paper, you can’t contain the grit or keep a level surface.
Both surfaces must be totally clean.
Pay a lot of attention to the end covers.
When you are convinced you have everything removed, pre fit the gasket so that you know which way they fit. I kept the spacer stops in place until I knew exactly which way they fit up. Infact I didn’t cut them until the last minute.
Buy a superior sealant, I only ever use Yamabond since Honda stopped selling theirs.
I have used this for years on cars and even old Brit bikes that are designed to leak oil.
Apply a thin even coat to either the gasket ( simpler) or the metal, not both. Assemble as quickly as possible, use a short metal straight edge like an engineers SS 150mm rule to ensure the end cap area is flush ( this is a Leakey area, use a torque wrench, you will over tighten these small bolts without one.
Leave over night, recheck the torque before doing the end caps. Same procedure, not too much sealant, theoretically the gasket is sufficient, but with old castings and engines they need a little help.
PS start tightening the covers from the middle out.
Put it all back together, let it sit for a few hours before starting up.
Just take your time.
Michael
Too many motos and cars, not enough life left!
Re: Replacing valve cover gaskets
Gaelicguy, thank you for the detailed instructions. Few more questions for you:
What is the torque spec for the nuts/bolts securing the end caps?
Can I take the entire distributor unit off as one piece or do I need to take the cap off from the metal housing and then take the housing off?
Do I need to drain any fluids from the engine - I wouldn’t think so.
I’m going to change the gasket on both left and right valve covers. The other valve cover appears simplier as I don’t have to mess with the distributor but anything specific to the right side cover?
What is the proper finish / color of the valve covers on a 67 spider? Mine are matte black which could be decades of dirt and grime or they are suppose to be matte. Since I have them valve covers off, thought I would have them cleaned up.
Thanks, this is great information for me.
What is the torque spec for the nuts/bolts securing the end caps?
Can I take the entire distributor unit off as one piece or do I need to take the cap off from the metal housing and then take the housing off?
Do I need to drain any fluids from the engine - I wouldn’t think so.
I’m going to change the gasket on both left and right valve covers. The other valve cover appears simplier as I don’t have to mess with the distributor but anything specific to the right side cover?
What is the proper finish / color of the valve covers on a 67 spider? Mine are matte black which could be decades of dirt and grime or they are suppose to be matte. Since I have them valve covers off, thought I would have them cleaned up.
Thanks, this is great information for me.
- Tobi
- Site Admin
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- Dino: Fiat Dino 2.4 Coupe
- Location: Upper Palatinate - Bavaria
Re: Replacing valve cover gaskets
Interesting discussion! Regarding the finish of the valve cover, have fun reading this thread: http://www.fiatdinoforum.org/viewtopic.php?t=564
The covers a just passivated magnesium, which gives them a brown finish. There is a good picture from a NOS head in one of my posts at the end of the thread.
I'd suggest to gently clean your covers and have another look on them.
The covers a just passivated magnesium, which gives them a brown finish. There is a good picture from a NOS head in one of my posts at the end of the thread.
I'd suggest to gently clean your covers and have another look on them.
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- Posts: 156
- Joined: Thu Feb 04, 2021 5:50 pm
- Dino: Fiat Dino 2.0 Spider
- Location: NE Washington, USA
Re: Replacing valve cover gaskets
First off, thanks Tobi for the link regarding valve covers. Very informative. I’m attaching a pic of my car which has 53k on it. Chassis #665. This car was stored from 1987 to when I recovered it in 2022. It’s unlikely they were ever off based on the dried oil and perfect nuts.
I have to agree, the covers were probably gold pacified. I’ve had lots of motos with exotic metals and this colour of pacification always ends up a dull grey/ brown colour.
I have to agree, the covers were probably gold pacified. I’ve had lots of motos with exotic metals and this colour of pacification always ends up a dull grey/ brown colour.
Too many motos and cars, not enough life left!
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- Posts: 156
- Joined: Thu Feb 04, 2021 5:50 pm
- Dino: Fiat Dino 2.0 Spider
- Location: NE Washington, USA
Re: Replacing valve cover gaskets
Now Dennis
No need to drain any fluids, if the engine has been standing for some time you will have minimum oil left in the heads.
You can remove the distributor in one piece( recommended) just be sure to mark its position.
As for the torque, I won’t give a number if my head ( the one between my ears) my car and manuals are on a ship heading to Portugal. But they are 10mm nuts so you easily overtighten.
Could someone pleas check the torque values from the Fiat manual.
Thanks
Michael
No need to drain any fluids, if the engine has been standing for some time you will have minimum oil left in the heads.
You can remove the distributor in one piece( recommended) just be sure to mark its position.
As for the torque, I won’t give a number if my head ( the one between my ears) my car and manuals are on a ship heading to Portugal. But they are 10mm nuts so you easily overtighten.
Could someone pleas check the torque values from the Fiat manual.
Thanks
Michael
Too many motos and cars, not enough life left!
Re: Replacing valve cover gaskets
What’s the best way to disconnect the throttle linkage from the rod that revs the carbs?
Re: Replacing valve cover gaskets
Proud to share that the job is complete, I put everything back together and now the car won’t start. I’m guessing there is an issue with the distributor which I had to remove from the engine to remove the valve cover. To be clear. I didn’t remove the distributor cap or the plugs but rather I disconnected the distributor housing from the engine. I had to reset the distributor coupler spacer (#2 in picture) when I reattached so perhaps that the distributor isn’t in the correct setting? The car tries to start but won’t turn over. Any advice? I’m confident all the plug wires are attached properly.
Re: Replacing valve cover gaskets
Try: Distributor out, Turn Distributor Drive at back of Distributor 180 degrees, back in and start. If you are Lucky that was it, if not you have mounted Nr. 5 by 90 degrees wrong. Look and understand how the Distributor Drive Works. In your picture, number 5 can be mounted in four positions, 2 of them are correct, 2 of them wrong. Must be correct positioned related to crankshaft. If you have Not removed number 5 it can only be the 180 degree thing if Engine ran before…
Thats why Michael advised in his earlier thread to mark the Position of the things you disassemble before
Thats why Michael advised in his earlier thread to mark the Position of the things you disassemble before
Re: Replacing valve cover gaskets
ThomasK
Full disclosure - I am a financial advisor with just enough mechanical courage to attempt a valve gasket change but not enough experience to debug a distributor. When you say “Turn Distributor Drive at back of Distributor 180 degree”, I am interpreting that to mean that I need to remove the distributor cap from the distributor and turn the rotor 180 degrees. Is that correct? I never removed the distributor cap from the distributor when I changed the gasket nor did I remove or even touch part 5 in the picture. These may seem like dumb questions but I’m in unchartered water here but determined to get this car running again because it was before the gasket change.
Full disclosure - I am a financial advisor with just enough mechanical courage to attempt a valve gasket change but not enough experience to debug a distributor. When you say “Turn Distributor Drive at back of Distributor 180 degree”, I am interpreting that to mean that I need to remove the distributor cap from the distributor and turn the rotor 180 degrees. Is that correct? I never removed the distributor cap from the distributor when I changed the gasket nor did I remove or even touch part 5 in the picture. These may seem like dumb questions but I’m in unchartered water here but determined to get this car running again because it was before the gasket change.