Fun with a DOHC

[Mogobs30th]

Most know that I have a 1995 Monte Carlo Z34. I recently learned that I had an intake manifold leak, so I have been working on it the last few hours. Here's some pics before.....

http://i33.photobucket.com/albums/d6...irebird017.jpg
http://i33.photobucket.com/albums/d6...irebird006.jpg
http://i33.photobucket.com/albums/d6...irebird004.jpg

And after....

http://i33.photobucket.com/albums/d6...irebird022.jpg
http://i33.photobucket.com/albums/d6...irebird020.jpg
http://i33.photobucket.com/albums/d6...irebird021.jpg
http://i33.photobucket.com/albums/d6...irebird018.jpg

Fun times just for an intake air leak.

BTW, this is also an attepmt to play with my digi cam, photobucket, and a new avatar. :D

[3.4 slow to go]

that's some nasty looking carbon buildup in them intake runners. ever hear of "Sea Foam"? [img]tongue.gif[/img]

also looks like gm's attempt to copy f*rd's 3.8 intake using square runners

[Mogobs30th]

Originally posted by 3.4 slow to go:
that's some nasty looking carbon buildup in them intake runners. ever hear of "Sea Foam"? [img]tongue.gif[/img]

also looks like gm's attempt to copy f*rd's 3.8 intake using square runners

Even Seafoam only goes so far. Those runners are getting cleaned with some brake cleaner before they are reinstalled.

Still got to yank out the O2 sensor behind that massive head and cam carrier.

[3.4 slow to go]

seafoam, an ounce or 2 every fill up to clean that shizz off in the future

[Camaro Dom]

how did you figure out you had an intake leak?

[Mogobs30th]

Really loud hissing coming from the passenger side, starting up horribly in the mornings when it was cold, and a leaned out O2 sensor.

I think what had happened was that the plug wires were changed some time ago before I bought the car. In order to change the plug wires on a 3.4 DOHC motor, you must remove the upper plenum/throttle body. I think when that plenum was removed and then put back on, it wasn't torqued down right, and the bolts began to slowly back out over time, creating the air leak. But I also want to make absolutely sure it isn't also the lower manifold that isn't leaking, so I am also changing out those gaskets as well.

[ December 25, 2005, 10:13 AM: Message edited by: Mogobs30th ]

[shenanigans]

man becareful of that motor... its a miniature nightmare.

[Mogobs30th]

Originally posted by shenanigans:
man becareful of that motor... its a miniature nightmare.

Actually, so long as you don't start messing with the cam carriers in any way, or the timing belt, the car is surprisingly easy to work on. You wouldn't think it by looking at it together, but it really wasn't too hard to take apart (compared to a RWD 3.8l). Every bolt is a 10 mm or 8mm. But once you mess with the cam carriers, its a whole other ballgame. I honestly wouldn't want to take the heads off or change the timing belt without some kind of help along the way, not to mention the specialized tools needed to change the belt or take those heads off. Only other part of the car that *MIGHT* require removal of the rear head is the alternator, because of its odd location.

[shenanigans]

alternator is a *****, and it goes out pretty often do to excess heat of its odd location.

battery is kind of rough for a battery but not insane, I have seen worse.


But timing belt always took it in for that, and still had 2 snap, one on a the original motor with 52k miles, pushed valves into pistons...

then the 2nd motor, had 30k on it when put in, made it to 47k, then we sold it and 5 months later same thing...

that car was definitely one of the most unreliable GMs we ever owned. Hell anything.

but ours was a 94 grand prix GTP

[12secondv6]

Port job?

[Mogobs30th]

Originally posted by 12secondv6:
Port job?

If I had a Dremel and time to do the port job it would definitely be considered. I do think a port job a a much more free flowing intake would help quite a bit. I can only port it so much though, because the throttle body and the plenum are all one piece.

As for unreliability of the car, that can be somewhat agreed upon. But I am not sure about it being poor. I think the engine was designed very poorly, but so long as you are on top of the maintenence religiously the engine seems to do ok. Only thing I have ever had to do to this car other than normal oil changes is replace the positive battery cable, which was shot due to a massive amount of corrosion. But again mine is a '95, I think by then most of the bugs were worked out by that year before they scrapped it for the 3.8l.

[3.4 slow to go]

save up some seirous $$$$$$$$ and extrude hone that bytch.

[Mogobs30th]

Well, after enough cursing, throwing things, and trashing stuff, I managed to get it running right for the first time in months. PITA though. Easy to take apart, hard to get it back together.