some stupid questions about heads and gaskets

Cox Abele

Registered User
I may have just wasted some money. Luckely the engine is still on the stand and only half together. Here's what I'm dealing with...

I'm using Felpro 9642-pt1 gaskets. The motor is an unknown. It was rebuilt once before I bought the car, but I pulled everything as it wasn't running when purchased. Good thing because the lower bearings were trashed, so I've been rebuilding.

The heads on it are new with the last rebuild. The coolant passages were very clean. I installed the passengers side head and found that my spark plugs are angled foreward. Is this normal? I clear my headers, but am not used to seeing the spark plug angle towards the front. Whats the deal? does this engine have two types of head (one for the left, one for the right?)

Secondly, I fear that I may have blocked my coolant passeges on the drivers side head. I failed ot double check when installing the gaskets. Are these heads full flow like a 5.0, and use the gasket to block off the front most coolant passages? I can see a very small part of gasket near the manifold, so I can identify what way I laid them down and determine where my gasket openings are for the coolant jackets, but where on our heads are the jackets, front or back?

This is just a stock rebuild, so I'm using TTY felpro bolts torqued to 62 ft-lbs. I wouldn't think about reusing the HGs, but will I have to buy all new bolts just to verify my junk won't overheat?
 
12 views and nothing?

I guess I need to make this a bit easier.

1.) My passenger side spark plugs point toward the radiator. My drivers side plugs point at the firewall. Is this normal?

I've not delt with angled plugs in so long...

2.) It looks like I've got the water jackets blocked in the rear of the drivers side, but open in the front. I haven't fired the engine yet or installed the intake. Do I just need new head bolts (already torqued, felpro) and a gasket? Everything was dry mounted, Lucas on the threads and a bit of thread sealer.
 
yes the spark plug angles are correct. mine are the same way. i think it makes more ease of removal.

not sure about the coolant passages tho....
 
Like everyone else has already said the heads are the same side to side. Also, the head bolts are NOT REUSABLE. You either need to purchase new head bolts and follow the torqueing procedure in a haynes manual or similar. Personally, I would convert over to a ARP head stud kit, as its reuable.

Chris
 
In our motors the head gaskets control the coolant flow from the block to the heads, with the largest opening being at the back of the motor.

It sounds like you may have got the drivers side backwards.
 
Arent the Felpro gaskets marked Front on them? Front always goes to the front even if it winds up on the bottom of the gasket. At least thats the way I remember it.
 
2.) It looks like I've got the water jackets blocked in the rear of the drivers side, but open in the front. I haven't fired the engine yet or installed the intake. Do I just need new head bolts (already torqued, felpro) and a gasket? Everything was dry mounted, Lucas on the threads and a bit of thread sealer.

You should obey the markings on the gaskets. They will either state UP or Front. Front goes to Front regardless. On the SC deck that typically means the front coolant passages in the block are 'blocked'. The coolant passages are opened slowly as the coolant flows to the rear, where the passages open up allowing the coolant to flow through the heads.
 
I may have just wasted some money. Luckely the engine is still on the stand and only half together. Here's what I'm dealing with...

I'm using Felpro 9642-pt1 gaskets. The motor is an unknown. It was rebuilt once before I bought the car, but I pulled everything as it wasn't running when purchased. Good thing because the lower bearings were trashed, so I've been rebuilding.

The heads on it are new with the last rebuild. The coolant passages were very clean. I installed the passengers side head and found that my spark plugs are angled foreward. Is this normal? I clear my headers, but am not used to seeing the spark plug angle towards the front. Whats the deal? does this engine have two types of head (one for the left, one for the right?)
This is normal. Heads are universal so one side points forward and one side points back.
Secondly, I fear that I may have blocked my coolant passeges on the drivers side head. I failed ot double check when installing the gaskets. Are these heads full flow like a 5.0, and use the gasket to block off the front most coolant passages? I can see a very small part of gasket near the manifold, so I can identify what way I laid them down and determine where my gasket openings are for the coolant jackets, but where on our heads are the jackets, front or back?
Open passages to the rear.
This is just a stock rebuild, so I'm using TTY felpro bolts torqued to 62 ft-lbs. I wouldn't think about reusing the HGs, but will I have to buy all new bolts just to verify my junk won't overheat?
If you only torqued the bolts to 62 ftlbs then there will be no issue with reusing them because the proper torque procedure is to torque the bolts to spec and THEN add another 90-110 deg rotation. This is the part where you stretch the bolts. If you haven't done this yet then you can still use them.
 
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This is normal. Heads are universal so one side points forward and one side points back.
Open passages to the rear.
If you only torqued the bolts to 62 ftlbs then there will be no issue with reusing them because the proper torque procedure is to torque the bolts to spec and THEN add another 90-110 deg rotation. This is the part where you stretch the bolts. If you haven't done this yet then you can still use them.


Interesting. My engine is a 91 if that makes a difference. I was using the specs listed in my chiltons and it read nothing about an additional 90-110, just final torque of 59, but I know my wrench may be a bit off, so I opted to give it 3 more ft-lbs over perscribed,

Can you get me the proper torque sequence?
 
. On the SC deck that typically means the front coolant passages in the block are 'blocked'.


If I may jump in for a ?.......So the driverside head gasket blocks the front coolant passage and forces the coolant to go to the rear....

If so this is interesting......My blown head gasket on the driverside seems to have got hot and soggy and caused a weak link from the blocked galley and the metal cylinder ring...

F1
 
If I may jump in for a ?.......So the driverside head gasket blocks the front coolant passage and forces the coolant to go to the rear....

If so this is interesting......My blown head gasket on the driverside seems to have got hot and soggy and caused a weak link from the blocked galley and the metal cylinder ring...

F1

Both sides do the same.. the water jacket openings are closed at the front but open up to full size by the time they get to the back.
 
Do they sell a gasket that doesnt do this or one with a restrictive opening....Or is the head blocked as well...I understand.....maybe..... the reasoning for the coolant to the rear....

Thanks

J....
 
The purpose of the port design in the head , block, and gaskets is to promote coolant flow through the engine. If this wasn't done, hot coolant would be stuck at the rear of the block as a circular flow would be created only in the front half of the block.

In fact, it is this type of flow common in most engine cooling applications. Water pump on the front pushes coolant into the front of the block. As this heats up and due to the flow of the pump, the fluid raises up through the engine into the heads where it is extracted and pushed through the radiator and back into the engine.

The LS1 design of Chevrolet (part of a lawsuit with Evans Cooling Systems) allows coolant to enter the heads first, then drop down to the block in a reverse flow system improving head cooling.

This link is to a thread where the various head gaskets people have used and their designs:
http://www.sccoa.com/forums/showthread.php?t=72873&highlight=head+gasket+mls

For my 90 that blew the head gasket I just used the Felpro upper kit and the stock replacement head gaskets, but with ARP studs. 3 years later it's still working fine after quite a few passes down the track at 11psi.

For my 93 that I rebuilt, I used the 9262/3 MLS Permatorque gaskets (98 mustang application) and ARP studs. Only about 5 months on that engine so far, and 7 or 8 passes at 12psi.
 
The SC coolant passages are different from a NA 3.8 Thunderbird, right? Are the later NA 3.8s / 4.2s (meaning 98+ Mustangs, F-150s, Windstar / Freestar) the same coolant passage design as the SCs?
 
early model N/A motors have a different coolant passage layout with more coolant passages around the bores. The late model heads adopted the SC layout as well as some other improvements. Supposedly a late model 3.8 head is better than the SC head. It is supposed to have a better heat treat, thicker deck, and uses smaller 7mm valve stems.

Kevin Leitem bought a set of them from SuperSix for his car.
http://www.sccoa.com/forums/showthread.php?t=95742&highlight=mustang+head
 
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