-
#1
Series 3 lower exhaust manifold replacement
SE Level Member
01-24-2020
04 GTP blowing smoke out of the lower /rear exhaust manifold so I'm trying to replace the gasket. There are 100s of videos on intake manifold replacement but I can't find a single one regarding the exhaust manifold replacement. I know it's sandwiched between the engine and firewall and I had a hard enough time before just accessing the flange to attach a new downpipe a few years back, and the manifold looks almost inaccessible from any angle. If anyone has seen a good video or tutorial please let me know before I die from CO poisoning.
-
#2
Re: Series 3 lower exhaust manifold replacement
Turbo is the way to go.
01-24-2020
Take the downpipe off and get the cross over loose or out of the way. Then unbolt the dog bone mounts on the front of the engine and remove them. Take a rachet strap and hook it somewhere on the front rad support and the rear of the engine by like the alternator, you should be able to pull the engine forward a few inches for more room. But the transmission in neutral when doing this so it can rotate as much as possible.
Then kinda lay on the engine to remove all the exhaust manifold bolts. Some rear manifolds actually crack too, so it could be leaking there too.
SMGPFC Member #1
-
Post Thanks / Like - 0 Thanks, 1 Likes, 0 Dislikes
-
#3
Re: Series 3 lower exhaust manifold replacement
01-24-2020
13 mm ratcheting box wrench will get 1/2 the bolts off way easier then a socket wrench.
search yt for header installs. some show them taking the old stock stuff off. the cross over bolts will likely break and the two down pipe bolts can also strip or break. so be ready with some new bolts, nuts and a drill and bit.
98 Buick Regal GS, F body brakes, Caddy STS wheels, tinted tails
L36 bottom end, lightly ported heads, 1.95 roller rockers, headers, gen 5 N* 3.0 pulley, FSIC, 42 lb injectors, a BrandonHall rebuilt trans, DHP tuned and AEM water/Meth injection https://goo.gl/gpV5kW
-
Post Thanks / Like - 0 Thanks, 1 Likes, 0 Dislikes
-
#4
Re: Series 3 lower exhaust manifold replacement
SE Level Member
01-25-2020
Thanks. While I'm looking up videos, initially it looks easiest to just lower the sub frame .with down pipe disconnected it doesn't look like anything else will be in the way. What do you think?
-
#5
Re: Series 3 lower exhaust manifold replacement
01-25-2020
i pulled mine out the bottom with the frame lowered, but ive seen a vid where the guy pulled it right up the top like nothing.
you need a couple foot of extensions for the down pipe bolts. and taking the air filter box top and the intake tube will open up the lower cross over bolts. be best to start lubbing them up for a week in advance then try to break em free when the exhaust is good and hot.
98 Buick Regal GS, F body brakes, Caddy STS wheels, tinted tails
L36 bottom end, lightly ported heads, 1.95 roller rockers, headers, gen 5 N* 3.0 pulley, FSIC, 42 lb injectors, a BrandonHall rebuilt trans, DHP tuned and AEM water/Meth injection https://goo.gl/gpV5kW
-
#6
Re: Series 3 lower exhaust manifold replacement
SE Level Member
01-25-2020
Anything specific needs to be disconnected if I lower the frame besides down pipe which was easy part? I've only lowered one at the junk yard so didn't care what happened to it.
Thanks again for the info.
-
#7
Re: Series 3 lower exhaust manifold replacement
01-25-2020
only drop it like 2 inches or so. or you can pull the shaft off the rack apart. why up the top might be best. headers you need to lwer the frame, stock r and r, not so much.
take the spark plugs out first too or you'll break em.
98 Buick Regal GS, F body brakes, Caddy STS wheels, tinted tails
L36 bottom end, lightly ported heads, 1.95 roller rockers, headers, gen 5 N* 3.0 pulley, FSIC, 42 lb injectors, a BrandonHall rebuilt trans, DHP tuned and AEM water/Meth injection https://goo.gl/gpV5kW
-
Post Thanks / Like - 0 Thanks, 1 Likes, 0 Dislikes
-
#8
Re: Series 3 lower exhaust manifold replacement
Donating Users
01-25-2020
I took out the manifold studs too. Think they are 5.5mm? That way you can slide the manifold right up without trying to get it back far enough to clear the studs.
Top Swapped 01 Imp
VS (very small?) cam, SD Headers, 2.8" pulley, 29°, ported everything, E85, AEM water/meth, Deka 60's, HPT tuned
-
#9
Re: Series 3 lower exhaust manifold replacement
SE Level Member
01-29-2020
Thanks for the help. Here's what I found out which may help others in the future. I found it best to use a bottle jack to move the engine up about 6 inches then strap it down with my rachet straps to hold it there. The header bolts are not actually 13 mil as purported, but 1/2 inch which fits very tight and prevents stripping them as I did to one of the heat shield bolts which I then had to saw the top off. For the rear crossover bolts which often get broken, yes mine broke too. My solution was to get some coupling nuts about an inch long, and some fresh studs from the hardware store, and couple the new stud on to attack the crossover. I'll add a picture of this so people can see the easy $7.37 painless solution to when they break.
Having done all of that and spending about 16 hours over 2 days of backbreaking work, mostly trying to loosen all those bolts which took all my strength, I didn't solve the problem of smoke, oil, and gas spewing out apparently above the manifold, so I'll post a separate thread on that and hope to receive some help there too. Thanks again.
