• The site migration is complete! Hopefully everything transferred properly from the multiple decades old software we were using before. If you notice any issues please let me know, thanks! Also, I'm still working on things like chatbox, etc so hopefully those will be working in the next week or two.

Engine tips and tricks while motor is out

green97

New member
I am getting a used L67 engine with 97k on it and will be installing it in my 02 very soon. Before I do it I want to address all issues with gaskets and seals while engine is out of the car.

My service manual says I need a special tool to install the rear main seal. Are there any tips or tricks on this install? Do you really need the special seal installer? Any alternative tools that can be used? Is the rear main even worth changing?

I have already purchased the following items...
felpro lower conversion gasket set, (oil pan, rear main, front/rear cover gaskets)
ac delco aluminum intake gaskets
dorman aluminum elbows
blower gaskets
egr gaskets
valve cover gaskets
valve seals
exhaust gaskets
water pump
engine and trans lower mounts

Would you replace valve seals? Please advise on anything that you would replace or freshen up while the motor was out. I also have a transgo kit with transmission currently out. Should I install the rest of the parts to it?
 


I would just delete the EGR; not worth jacking with.

Make sure you got non-fluid filled trans/motor mounts. You want the solid rubber ones.

I'd take apart the front cover and have it hot tanked at a machine shop; along with having the shop either rebuild the heads; and even have them cleaned up or ported while they're there. If you're having the heads even looked at...I'd put at LEAST new L76 springs on it, or LS6's. Also I would do new bronze guides and Viton or Felpro seals. Since it's out; I wouldn't hesitate to do it while you're there.
 
I got the hydraulic engine mount and a solid trans. Why the solids?

I need to get this thing running ASAP as its my work commuter car. I can rebuild my old heads as time and money allows and swap over later if needed.

My main concern was whether I should change the rear main seal, front seal and can I use a normal seal driver to do it instead of the gm tool. Also wondering if its worth installing the rest of my transmission kit.
 
The solid mounts help keep the engine from moving when under load. Guys on this forum offer mixed reviews. Some say that they are a must, some install them only to remove them. The main value-add for the solids is that they don't bust and leak fluid like the hydraulic ones do. The solids don't need replacing. Where as the hydraulic ones do because they will bust at some point. The main complaint for solids is excessive vibration, as the solid mounts don't absorb them as well. I'm in need of a engine mount as well, and after some thought I'm going to install the hydraulic mounts. I personally prefer the smoother ride, and limited engine vibration.

I strongly suggest doing the front and rear seals. Absolutely. There are countless threads from noobs asking for help identifying a mysterious coolant leak around the passenger side. It's almost always the front seal. And I know that the rear seal goes out as well. Not sure about the seal driver tool....

As far as the transmission kit, you either install all of it, or none of it. You can't really install parts of it. You could in theory, but you just don't. So not sure how to advise you on that one. I guess just put the whole thing in.
 
I've only had to replace a few front and rear main oil seals.
The number one gasket to replace is the rear cover gasket that the rear main seal rides inside of this gasket splits and causes external and internal oil and coolant leaks and out of 20 engines I've torn apart 14 needed that gasket desperately
 
I watched a few youtubes and found some forums on the trans kit and everything suggested do what you can with trans in the car. But the kit came with a few other parts that I was curious about. Here it is...https://www.amazon.com/Wellington-Parts-Corp-T84167G-Transgo/dp/B008XO9ATC

I will definitely replace the cover seals. The rear main is to big for my seal driver set. The gm service manual shows a tool that draws the seal in with a bolt. I was hoping somebody could elaborate on whether a driver of the correct size would work instead of the special gm tool. Worst case I could take the cover off and take it to the dealer and have them put it in. In the mean time I might bite the bullet and buy the tool or a driver set that fits. Rear main seal bore is about 3 7/8" od and roughly a 3" id seal.
 


You know what, you're right. The trans-go kit does come with hardware for 3rd and 4th gear, now that I think about it. Been a year+ since I did mine. I didn't install that extra stuff, most dont.
 
The trick so to say with the rear seal is making sure you set it to the same depth as the original seal was... There's a lot of forgiveness but it's easier to replace the seal onto cover while off engine. Just use some form of accurate measuring to ensure you're at same spot. I scribed the seal channel to do it in addition to measuring it. That's just me.

Felpro is ok, but for the Front Seal, I would recommend "GM" only! On the oil pan, use some Black RTV, lol. Front and rear covers, make sure you use some RTV on the lower 20% as this is where they sometimes leak from. My rear cover was fine on last engine, replaced gasket and seal anyway (cam build). But as mentioned, there's a bunch of threads out there to guide you.
 
I am going to have engine out soon to get a new TEP tranny installed. I am on GM parts direct and i see the front and rear main seals, but i dont see front/rear cover seals. Does anyone have a link to them? I would like to stick with ac delco if possible.
Thanks
 
I am going to have engine out soon to get a new TEP tranny installed. I am on GM parts direct and i see the front and rear main seals, but i dont see front/rear cover seals. Does anyone have a link to them? I would like to stick with ac delco if possible.
Thanks

rockauto.com should have delco seals
 


thanks for looking rickisrad. I just looked on gm partsdirect again, amazing what you find when you aren't doing it at midnight, and found these.

http://www.gmpartsdirect.com/pontia...ine-cat/engine-scat/?part_name=rear-main-seal

http://www.gmpartsdirect.com/pontia...e-cat/engine-scat/?part_name=front-cover-seal

http://www.gmpartsdirect.com/pontia...cat/engine-scat/?part_name=front-cover-gasket

looking at the diagram of the motor in these links, it looks like pt 34 is the front seal, but it is not listed in the listing of parts by number?
I can't find the rear cover seal, or is it a gasket like the pt 12587003 is for the front above. Do the covers have seals or gaskets? are these the right ones?
Thanks
 
I just finished getting my engine back in last weekend. Been dealing with some minor issues this week. I replaced all the gaskets and seals with felpro stuff except for head gaskets and valve stem seals. New ac delco water pump. I can't sat I have any tips or tricks after doing it all. I painted the block and cleared my aluminum stuff after cleaning everything for days. Swapped sensors over from original motor knowing they worked fine. Make sure you have a good razor blade scraper with sharp blades for removing gaskets and a shop vac to keep stuff out of places the old gasket material doesn't belong.

I am still dealing with trying to get the lower coolant elbow sealed up it was a constant drip, now a light drip after shutting off. I removed the tensioner and had missed cleaning some coolant chalk out of the holes so I used some sand paper in them with some success.

I was also getting code p0300 random misfire. GM service manual says if you have swapped engines pcms or crank sensors etc to do a crank relearn procedure. I ended up doing that using an hp tuner scanner and fixed the random misfire issue. So far runs good. Had to replace a few squeaky idler pulleys too. I never did the extra transmission stuff. I did replace both lower control arms as one side had a front bushing falling out. Installed 12" rotors and impala caliper brackets too. Had to buy new abs wire fasteners for new control arms as old ones broke off, although zipties would work I like to use the correct stuff. I also replaced the sc coupler and oil. Cleaned MAF and throttle body.
 
As far as the rear main, I have access to a machine shop at work and found a scrap piece of tubing and had it machined to the OD needed. I scribed the original seal depth and removed/installed with cover off. If I had done the ID of the tube correctly I could have used a piece of plate and the proper sized bolts to install the seal while cover is on by threading bolts into crank and pulling installer in with bolts.
 


Back
Top