A little history , bought our 95 Bonnie in feb. 2004 for 650$ 134,000 miles , towed it home , changed timing set , crank and cam sensors , plugs , wires. Got it to run but it was showering coolant out the exhaust. Came on here and figure out to get the aftermarket upper intake. Put it on , same outcome from the exhaust. Pulled the heads off and took to machine shop Front far right piston had 4 or so holes in it so I pulled the pan , all the pistons. Had 3 cracks in the front head water jackets. Anyway , I put 1 new piston in , new rings , new gaskets , new rod bearings , but could only get one main cap off , the one nearest the tranny. I never replaced the main bearings because of it.

I know when coolant mixes with oil it becomes acidic and trashes the bearings. Well , last week I start getting a rod knocking , No doubt in my mind that it could be anything else.
So I am going to rebuild her the right way this time , anyone know of this phantom special tool to take the main caps off , they are recessed into the block? We tried all sorts of stuff last time and finally gave up.

Also it'* been a while , anyone have the main and rod torque specs? I still have my trusty torque angle meter!

Sorry to post so long , I haven't had a prob. other than the starter since I fixed the motor 3 weeks after buying it which was prob. the last time I posted. "Shameless plug" anyone with a 4th gen G body check out www.montecarloss.com Sorry , I had to!!!

Most torque specs are in Techinfo. Do NOT mix up your rod caps. Number them as you remove them, or you're hosed.

I strongly suggest you get Chilton'* #28200 before going any further.

I have the chilton manual for my year of bonneville and it shows no crank or rod torque specs. anywhere in the manual , I looked prob. 10 times thru the whole thing! I had to call a pontiac dealer to find them out last time. I wrote them down and threw the info away about a year ago. Lesson learned not to throw out any info on your car! I have built a few chevy v8'* so I know the fundementals of it all but I've never delt with swedged main caps before. I heard there was a GM tool to take out the main caps on the 3.8 series 2. I believe it because I couldn't get them out nearly 2 years ago and need to know how to get them out this time around!

Our bonneville has been the best car we have ever owned , including my prized possesion , 1985 Monte Carlo SS that I've had for almost 4 years with over $7,000 put into it. We got the Bonnie in feb. '04 for $650 and put less than 1,000 into to get it back right. In those almost 2 years , I've bought a new starter , regular oil changes , tranny filter/fluid changes and new front brake pads , 2 fuel filter changes , 2 new front tires , one used front rim due to wonderful I-70 in St. Louis shoulders (cracked rim , nail in tire)

Awesome car though! I am looking for another one in the KC area. After I get this one fixed , it is gonna be my wifes daily driver and I want one for my daily driver !!!

Many main bearing caps will be wedged against the block because of the years of being torqued down to 100+ ft.lb. Take a good sized hammer, AFTER you have the bolts all the way out of course, and give both the left and right side of the main cap a slight whack. That should break them loose. I know i've had some very stubborn ones come through my shop. I'll see if i can find those torque specs for you also.

Also as for the main-bearings, i found this on a 3800 website: Cross-bolted main-bearing caps and a deep-skirt design improves stiffness to reduce noise radiated from the engine." So they are cross bolted.

Havn't been able to locate torque specs yet...

Hey guys...What is cross bolted?

From '95 FSM for VinCode K (p 6A8-49)

Use GM approved sealer at Number 4 main bearing cap to block surface

Number 4 main bearing cap must be installed flush with torque converter bolt heads or .010" forward of rear face of cylinder block to avoid interference with flywheel

Start main bolts by hand. Make sure bottom of cap is parallel to bottom of channel. Torque all caps in equal increments. Do not tighten one cap completely at a time. Tighten bolts to 70 N-m (52 ft-lb) to fully seat caps. Loosen bolts 360* counterclockwise, then torque bolts to 20 N-m, (15 ft-lb) then 40 N-m (30 ft-lb). Using (torque angle meter) tighten bolts in steps: 35* + 35* + 35* for a total of 105*

Tighten side bolts to 15 N-m (11 ft-lb) + 45*

Tighten rod caps to 27 N-m (20 ft-lb) + 50*

The FSM suggests the following for removing the caps:

Notice: Main bearing caps are press fit and special care is required when removing the caps for service. Use locking type pliers clamped over the bolt hole portion of the cap for removal. Do not clamp between bolt holes and bearing surface as damage may occur to the cap. Any deviation from this procedure may cause damage to the cap and or the bearing, possibly resulting in future engine damage.

The main bearing caps have two small diameter long bolts into the side as well as the two big bolts through the bottom. If you don't know about 'em, you aint never gonna get the cap off! The bolt head is on the outside of the block on the Series II'*.

He'* got Vin K of course.... working on the fix, now

Also explains why side bolts were not pictured or mentioned for Vin L (doh!)

Thank you