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3400 ohv lower intake manifold gasket questions

B

Bjorn20

New member
I am currently gathering parts for a lower intake job on a 04 impala 3.4

I made a trip to a Chevy dealership to get an ac delco lower intake gasket kit, part number 89017559. Apparently, there is an updated, "aluminum", gasket now instead of the plastic design. The problem is, just by looking at the gasket through the packaging, it looks like it's plastic and NOT aluminum; but from a little internet exploring, gm only has 1 gasket for that motor, it sure doesn't look aluminum though (comparing it side by side to the fel-pro design). Also, the gm gasket does NOT come with any rtv, and its a 1 piece gasket (no rubber strips for the sides). So, does this gasket not need any rtv? Maybe its only the 3.8's that have the separate rubber strips?

All that being said, it makes me wonder if I should have just gotten the fel-pro gasket kit from oreilly that comes with pretty much everything and close to the same price as the gm gasket. Except this engine already had the lower intake replaced with the fel-pro kit and is leaking again (~20,000 miles later).

AC Delco gasket:
More Information for ACDELCO 89017559

Fel-Pro gasket:
More Information for FEL-PRO MS98003T



This guy looks interesting too for $90. Comes with everything, including manifold bolts, and valve cover nut grommets for which together are like an extra $30 alone. Although, I have never heard of the brand.
More Information for VICTOR REINZ MIS16259WB
 


IIRC the end seals on the 3400 are nothing but a nice stripe of RTV that you put down. Yes you want RTV, I'd suggest Permatex Ultra Copper. It's the one stop RTV.

Be careful when you do the gasket. Keep your pushrods in order or oriented so you know exactly which one came from which position...IIRC they are different lengths intake vs exhaust.
 
Well thats good to know. I'm still curiouse as to why it is leaking again. Only one way to find out I guess.

The gasket design/brand is still bugging me though. I dont even think ac delco makes the improved aluminum design for this motor. The fel-pro design looks a hell of a lot more like aluminum compared to the gm one.

I'm curiouse if I should replace the manifold bolts as well. Who knows, maybe they slowly backed out from the first LIM job.
 
I've never heard of a bolt issue... however it's a 3400 and I have no love for the dirty one or four hundred motors.
 
I don't think you need to replace your lim bolts, when I did my head gasket "for the 2nd time" I noticed the replacement fel pro plastic llim gasket looked like it was close to failing, around the runners its like a 2 piece design with the inner piece being very flimsy and it disconnected from the rest of the gasket. I didn't look for or find an aluminum replacement. Went with another fel pro kit and 1500 miles in so far so good.
 


My boyfriend had a 99 Grand Am with the 3.4 in it.
He ended up doing this 3 times before it went out the 4th time and he sold it.
I had a 97 Grand Am with the 3.1 in high school, did the LIM once and then in 08, both LIM and heads failed, so I sold it.

So Bill, I understand your love/hate relationship with them.
 
Did you use loctite on the mainfold bolts? My wifes 01 ga gt had it done at a shop before we were married lasted about 6 months before it leaked again. I changed it myself and it was fine when we sold it last month with 187K miles on it. My lim job lasted 2 years and was still fine.

Here is alum vs plastic gaskets

0427001802.jpg


Also there is no gasket that runs between the 2 heads just gasket maker.
 
dsmuts said:
Did you use loctite on the mainfold bolts? My wifes 01 ga gt had it done at a shop before we were married lasted about 6 months before it leaked again. I changed it myself and it was fine when we sold it last month with 187K miles on it. My lim job lasted 2 years and was still fine.



Also there is no gasket that runs between the 2 heads just gasket maker.
Click to expand...

I'm not sure about the loctite as I had another mechanic do the service while I was still on the clock.

Called gm, apparently the only design they make is plastic. So, I'm taking that one back and getting the fel-pro kit, which looks like a much better design anyway.

As far as the manifold bolts go, are those washers (for the upper intake I would assume) necessary? I've only seen one company (VICTOR REINZ through rock auto) that supplies 4 washers with the manifold kit. I would much rather get the stuff from oreilly than deal with shipping though.
 


V-R is a good gasket name. I just put their head gaskets, exhaust manifold gaskets, lower and upper intake gaskets.....in my 05 Jimmy. Used them on a few other jobs too. No issues with them thus far.

Jay
 
For the price difference between brands, the washers alone are $3 for a set 4, haha screw that.

Has anyone ever bought replacement car parts through amazon? Its like $30 cheaper than oreilly for this job, and about $10 cheaper than rock auto after shipping.

Also, do any of you replace the valve cover grommets since your already doing the valve covers (for this awesome 3.4 anyway) ?
 
This is a very common problem for all 3.1, 3.4 and a little less common but 3.8's.The upgraded set is still going to leak...eventually.but you should get somewhere bettewn 50,000 and 100'000 out of them before it goes again.Make sure all the surfaces are clean! i.e. free of oil and any debris. allow that bead of rtv(1/4 bead on both sides of valley) to set slightly before installing the lower intake back on as this is the most comment failure after replacement.as long as you torque it properly and in the correct sequence you should be good.A few things to look out for when doing this job...when you disconnet the fuel line from the rail be sure to replace the orange o-ring around the feed line as it does tend to leak if you dont and you will be quite angry if you have to take the upperintake back off after your all done to fix that.it is a special o-ring(fuel resistant) and comes with some of those intake gasket kits.if not DOORMAN HELP has them.also look at you timing chain gasket.is it leaking? these can also leak coolant and are much eaiser to do with all the manifold stuff out of the way.but in order to get it off you have to take the oil pan off.its probaly leaking oil to so this will take car of 90% of the places your engine leaks.A WORK OF WARNING!!! when you do the intake gaskets do not start engine untill you change oil! chances are coolant is in the oil pan from the intake.OH and these are known to knock after job is done if its been leaking awhile. why is a good question! but i dont know that one.they just do.also...if you havent done the head gaskets or thermostat yet i would go ahead and get that done while your in there(if you plan on keeping the car=) no point in doing all that work just to have to tear it all apart again when the head gasket blows! Good luck with that if you have any more questions about thuis job feel free to ask
 
^^ interesting facts to know. Every replacement gasket is going to eventually leak at some point in its life, but shouldnt leak again in 20k miles.

I have actually never seen anyone replace any o-rings in the fuel rail, nor have I seen/heard of a comeback from that leaking o-ring, but good idea. Now that I think about it, all of those jobs were done in a shop, so the mechanic probably didnt care about it as he was just trying to get it done as fast as possible. One thing I have seen leak on 2 different vehicles now, is some sort of an o-ring in a coolant line/pipe (connected by a plastic quick connect fitting) that goes into the back of the motor, almost want to say the block on the drivers side.

Sort of on a real tight budget, so I dont think the timing chain gasket, head gasket or oil pan is coming off. It would be a good idea though, just dont have the time and not in the budget at the moment. I didnt know the timing chain area even touched coolant, learn something new everyday.

Wierd, I have seen quite a few of these motors have milky oil before the service was even started and no knocking before or after. Once again, good to know though.

BillBoost37 also mentioned something about using permatex ultra copper instead of RTV for those LIM corners, would oreilly carry something like that?


edit: Is this the fuel rail o ring(s) you were talking bout?
http://www.rockauto.com/catalog/moreinfo.php?pk=88869

those are some expensive rubber o rings at $7 a piece lol. Although they are not orange.
 
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don't pull the lines off the fuel rail and you don't need to replace the o rings then. Orielly's would have copper rtv just ask them where it's at. Also make sure you change the thermostat or you'll regret it if you ever do need to change it.

Oh and don't worry about head gaskets or anything like that they don't need done and it's that much more work and money you have to throw into your car.

On my grandma's gp it knocked for about 15 min after i changed her intake gasket and the cam had scoring marks on it :(
 


I can understand the money situation. there just things i recomend to save time in the future.im not sure if these are your o-rings though. its hard telling over the computer.ever the original one is orange as was the one i replaced it with. i had to disconect the line at the fuel rail only because the bolt on the drivers side of engine that holds the fuel lines down wouldnt come out.as for the permatex ive always used the rtv black but to each thier own as long as its oil resistant.I think those plastic quick disconnect lines your talking about are to your heater core.Thats fun replacing
 
dsmuts said:
don't pull the lines off the fuel rail and you don't need to replace the o rings then. Orielly's would have copper rtv just ask them where it's at. Also make sure you change the thermostat or you'll regret it if you ever do need to change it.

I was wondering about that too. I don't remember if the thermostat housing has to come off or not on the 3400

On my grandma's gp it knocked for about 15 min after i changed her intake gasket and the cam had scoring marks on it :(

Did the motor stop knocking after 15 minutes or did it blow after 15 minutes of knocking? Considering you had it torn apart enough to look at the cam.
Click to expand...

pontiacgtp24 said:
I can understand the money situation. there just things i recomend to save time in the future.im not sure if these are your o-rings though. its hard telling over the computer.ever the original one is orange as was the one i replaced it with. i had to disconect the line at the fuel rail only because the bolt on the drivers side of engine that holds the fuel lines down wouldnt come out.as for the permatex ive always used the rtv black but to each thier own as long as its oil resistant.I think those plastic quick disconnect lines your talking about are to your heater core.Thats fun replacing
Click to expand...

The fix to this was to put some rtv around the area of the fitting and plug it back into the engine, no replacing of lines haha. Just weird that this line has leaked on 2 different jobs that I've seen, and yet the line was never touched in the entire service.
 
It stopped knocking and ran fine but about two weeks after i did that and a bunch other stuff to it she wrecked it so :( all my time was lost and her money spent
 
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