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420A 420a Headgasket Replacement

Nova95

Probationary Member
28
0
Jul 7, 2022
Kirbyville, Missouri
Hey guys. I'm in the middle of a head gasket replacement on my 96 RS. I've got most of the tear down around the engine done and I'm down to the timing components and finishing the intake manifold which has been the most pain in the a$$ so far. I've cracked the top bolts loose but I have literally no wiggle room so I figured I'd look around and see if there were any tricks online. I Read that if I unbolt the two stays, that the head and intake will come off as one, so I don't need to even bother with the intake manifold bolts. What?! Is it really that easy?!
 

99dsmer4g63

Proven Member
173
86
Sep 20, 2022
Shippensburg, Pennsylvania
If you disconnect the sensors, hoses and fuel lines yes, you can the leave the intake manifold attached and pull it as one piece if you desire.

It will be much heavier so I advise a friend to help pull it or have a engine hoist. Be careful if you reinstall it like this as well to not damage the head gasket from the weight of the two and mishandling it.

Also I replaced the intake manifold gasket to the head on my 95 rs when I was 16 so I know it can be done and I wasn’t too knowledgeable at the time so you may wanna try a little harder at getting to the lower bolts 😆.

-Daniel
 

97egl

Proven Member
443
212
Feb 6, 2014
Brownsburg, Indiana

BLACK'98DSM

Proven Member
3,763
1,359
Feb 9, 2019
Alabama
I always just leave the intake manifold, the headers, and the thermostat housing still bolted up. I can have the head up and out in an hour. It's definitely heavy this way though. I lifted it alone last time but am calling for help next time LOL
 

Nova95

Probationary Member
28
0
Jul 7, 2022
Kirbyville, Missouri
Thanks for that link about the head bolts! I disconnected the hoses, sensors, and the stays to pull the head and intake off as one. The sky bottomed out and it poured the rest of the day so that's all I got done. But when I was down there I briefly noticed the Alternator bracket seemed pretty high up. Is it attached to the block or the head? Does it need to be removed to pull the head/manifold as one or is it fine where it is?
 

Nova95

Probationary Member
28
0
Jul 7, 2022
Kirbyville, Missouri
An hour?! Wow yeah I've already made this job way longer than it needed to be after reading that. At least I can reassemble those things to the head in the apartment though and just put it back in as one. It's great to know for next time though. I've only done one other head gasket prior to this one and it was on a Honda and was so much easier for some reason.
I always just leave the intake manifold, the headers, and the thermostat housing still bolted up. I can have the head up and out in an hour. It's definitely heavy this way though. I lifted it alone last time but am calling for help next time LOL
 

BLACK'98DSM

Proven Member
3,763
1,359
Feb 9, 2019
Alabama
An hour just because I've done it a few times and already know what needs to be done. I don't remember how long it took the first time. I personally think the 420a is a much more simple engine than a Honda unless we're talking a single cam D16.
 

Nova95

Probationary Member
28
0
Jul 7, 2022
Kirbyville, Missouri
I bought these instead of using the head bolts. Just realized that it says 2.0t, Do I need to cancel the order or will these work?

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BLACK'98DSM

Proven Member
3,763
1,359
Feb 9, 2019
Alabama
I would use stock head bolts before chinabay head studs. Just my opinion.

-Daniel
I definitely agree. But on the contrary I would use ARP studs instead of OEM head bolts. They really make head jobs significantly easier and are also re-usable unlike head bolts.
 

Nova95

Probationary Member
28
0
Jul 7, 2022
Kirbyville, Missouri
Okay. Local part stores have to "Special Order" the stock head bolts and wouldn't get them for another two weeks so I'm pinched on what to do. Thanks for the input.
 

99dsmer4g63

Proven Member
173
86
Sep 20, 2022
Shippensburg, Pennsylvania
I definitely agree. But on the contrary I would use ARP studs instead of OEM head bolts. They really make head jobs significantly easier and are also re-usable unlike head bolts.
I agree 100%. This was just on the thought of using the cheap ones he had in the couple posts above. If you have the coin then yes ARP’s for sure. I personally run arp head studs on my car and my Cummins along with my cousins truck as well.( I do all his motor work)

The ARPs are the only internal motor fastener I would trust over something oem. But if your thought is to cheap out and use the chinabay head studs then just stay oem.

-Daniel
 

Nova95

Probationary Member
28
0
Jul 7, 2022
Kirbyville, Missouri
So does this look like a blown head gasket to you guys? Or was my problem not a head gasket?

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BLACK'98DSM

Proven Member
3,763
1,359
Feb 9, 2019
Alabama
So does this look like a blown head gasket to you guys? Or was my problem not a head gasket?

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See how the blue rubberized coating is missing between cylinder cut outs? And see the carbon build up on the deck surface between cylinders? Your cylinders were "sharing combustion" per say. Definitely not a healthy way for an engine to run.

Something I'll note though. As you can see the headgasket has clearly been replaced before. I don't think the gasket itself was the point of failure. It's likely that the head was not resurfaced by whomever previously did a headgasket job. And since that is an MLS gasket it does make a difference. So if the head was warped then the MLS gasket never had a chance at sealing. Or another theory could be that the head bolts were re-used or improperly torqued, thus warping the head and it not sealing. Either way, you need to get the head resurfaced before installing it with a new headgasket. It's a good time to do some valve seals as well.

And another thing, try and clean the deck surface and cylinder walls as much as you can before putting it back together.
 

Nova95

Probationary Member
28
0
Jul 7, 2022
Kirbyville, Missouri
See how the blue rubberized coating is missing between cylinder cut outs? And see the carbon build up on the deck surface between cylinders? Your cylinders were "sharing combustion" per say. Definitely not a healthy way for an engine to run.

Something I'll note though. As you can see the headgasket has clearly been replaced before. I don't think the gasket itself was the point of failure. It's likely that the head was not resurfaced by whomever previously did a headgasket job. And since that is an MLS gasket it does make a difference. So if the head was warped then the MLS gasket never had a chance at sealing. Or another theory could be that the head bolts were re-used or improperly torqued, thus warping the head and it not sealing. Either way, you need to get the head resurfaced before installing it with a new headgasket. It's a good time to do some valve seals as well.

And another thing, try and clean the deck surface and cylinder walls as much as you can before putting it back together.
Okay that's makes a lot of sense. The whole reason for replacing the head gasket was because she had a multiple cylinder misfire for a while and after chasing every other culprit it could of been to no end, I came down to maybe it was compression leaking between cylinders.
 

97egl

Proven Member
443
212
Feb 6, 2014
Brownsburg, Indiana
Okay that's makes a lot of sense. The whole reason for replacing the head gasket was because she had a multiple cylinder misfire for a while and after chasing every other culprit it could of been to no end, I came down to maybe it was compression leaking between cylinders.
For future reference before tearing the engine down you can do what's called a leak down test to determine if this is what is happening.
 

Nova95

Probationary Member
28
0
Jul 7, 2022
Kirbyville, Missouri
Do I need to use any special lube when installing these valve seals and valves or will motor oil work fine?
 

BLACK'98DSM

Proven Member
3,763
1,359
Feb 9, 2019
Alabama
Do I need to use any special lube when installing these valve seals and valves or will motor oil work fine?
I always use assembly lube or moly grease, whichever I have at the time. Make sure if you're installing new valves that you lap them.
 

Nova95

Probationary Member
28
0
Jul 7, 2022
Kirbyville, Missouri
If I'm just reusing the valves do they need to be lapped or just put them back where I found them?
 

BLACK'98DSM

Proven Member
3,763
1,359
Feb 9, 2019
Alabama
If I'm just reusing the valves do they need to be lapped or just put them back where I found them?
If you can mark each one and put them all back where they came from it would possibly be fine. But I would be safe and have the head pressure checked by a machine shop to make sure there's no leakage from the valves. Since you need it resurfaced anyway they should be able to do that for you as well.
 

Nova95

Probationary Member
28
0
Jul 7, 2022
Kirbyville, Missouri
I double checked timing tonight but I guess I should of quadruple checked. Car is turning over but no where near starting. Took the wheel off to rotate the crank to check timing again and now the crank won't even budge. I'm guessing I destroyed the valves?
 

BLACK'98DSM

Proven Member
3,763
1,359
Feb 9, 2019
Alabama
You would know if the pistons made contact with the valves. You would hear/feel it. For that to happen timing needs to be at least 2 teeth off, so not sure how you wouldn't notice that while double checking the timing. For right now pull the spark plugs and try to rotate again just to make sure it's not just stiff from compression. Where are you located anyway, I'll come get her timed up this weekend if you're close
 
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