: Replacing a Northstar in my 2003 Seville...what should I check for?



blueandred
04-02-13, 01:53 PM
Hey everyone, you have answered so many of my questions in the past without me having to even ask them, I figured it's time to actually ask! lol. long story short, my seville is getting a salvage engine installed with a 6 month warrentee. (HG issues, best route). Before the "new" motor goes in, what should I pre-emptivly repair/replace to avoid large repair costs after it's installed....like maybe replacing the TCC solenoid in my trans while it's out...?

Thanks!
-Kevin

2003 Seville SLS, 107,000miles

vincentm
04-02-13, 02:41 PM
Stud the replacement engine.., reseal it, replace CKP's, plenum duct, TCC solenoids and TCC seal.

All hoses, including heater hoses too, at least, i would

blueandred
04-02-13, 02:48 PM
Thanks vincentm, for the plenum duct are you referring to the the plenum on the TB between that and the manifold?

vincentm
04-02-13, 02:50 PM
Thanks vincentm, for the plenum duct are you referring to the the plenum on the TB between that and the manifold?

Yup.

blueandred
04-02-13, 02:52 PM
Thanks. it's on my to do list now.

Ranger
04-02-13, 03:29 PM
The plenum duct is no big deal. That can be done anytime it fails without much work. Considering it's a 2000+ I would definitely replace the TC, seal and solenoid. It's almost bound to fail (or leak) sooner or later.

Studding or inserting the replacement engine is up to you. Being a 2000+ engine it is less likely to fail, but there are no guarantees. Studding or inserting it will remove the possibilities of a future failure, but will add a good $1000 or more to the replacement cost. Tough choice.

blueandred
04-02-13, 04:03 PM
Thanks Ranger. I replaced the plenum on my wifes DTS with no problems so that's no big deal, just wanted to make sure we were talking about the same thing. it's out so it might be easier to do but i wasn't that difficult in the car either. my 2000 SLS started having too many issues when it hit 190k so I decided to get my current 2003 but it ended up having HG issues so the dealer is replacing the engine at their cost (my Caddy mechanic though). definately gonna do the TCC and the rear mains.

stoveguyy
04-03-13, 10:20 AM
How did u get dealer to replace ur motor?

blueandred
04-03-13, 02:20 PM
stoveguy, i bought it on agreement but with no warrentee, to not have leaks, drips or HG issues. (106k miles) it overheated 20 miles from the dealer. thougth it was air bubbles from new water pump they installed. leaked the next day. they fixed that leak, overheated again, new leak now...they fixed that leak...overheated again. took it to my local mechanic who's a caddy mechanic with his own shop...diagnosed bad HG. Dealer is paying him to install a used, with warrentee, motor they are shipping to him. no arguments,ever, from the dealer. excellent folks. they got stuck with a bad HG on a trade, sold it to me and are fixing the problem. This is the type of dealer that will get my return business! (even if they are 110 mile drive!) Pfeiffer in Grand Rapids MI.

stoveguyy
04-03-13, 02:48 PM
I know by 03 headgaskets were more reliable, but. How complete is new used motor? Coils, intake, accessories?

blueandred
04-03-13, 03:06 PM
it's a complete assembly. inspecting it tomorrow when it comes in. I'll probabaly pull the new water pump off my engine and swap it and it'll get new plugs before it goes in. that's why I was getting opinions on what to replace. pretty much what I thought but I appreciate the suggestions for sure.

Submariner409
04-03-13, 06:08 PM
I hate to say this off-the-cuff, but drop-in used Northstars can be a real crapshoot - with no 7's or 11's.

blueandred
04-03-13, 07:23 PM
Submariner409, yup, I agree but it's basically a freebee and my mechanic can inspect it the best he can. it has a warrentee at least so it helps my odds. Better than money out of my pocket. We're gonna run the vin when it shows up and get a history (what we can) on the engine. I do know it's coming from a trusted source. Otherwise, the car is in perfect shape. Besides, I've never played craps. lol. I'll definately post the results after I've had it running for awhile.

stoveguyy
04-04-13, 10:48 AM
If the exterior of motor looks good than that's all you can really inspect a motor on a skid.

blueandred
04-04-13, 03:33 PM
yup. I agree but it's the best option I have and it's not costing me anything but time. I just figure to up my odds I would replace parts that have tendancies to go bad but require extensive work do to having to pull/access the motor. TCC, Main seal..etc. it's out so the labor for me will be minimal. parts are cheap for these fixes. Good or Bad, the motor will not have a HG problem when I get the car back. OTher wise it's a ton of cash lost that I can't afford. Never know, I might get the original motor back...give me a project to work on, learn from. What I'm looking for is just some insight into what I could replace to up those odds for me. Thanks.

stoveguyy
04-04-13, 07:30 PM
A lot of oil seepage might point to a weak case half seal. Sure would be nice to put motor on stand, turn it over and reseal case. BUT it is a picky job. U should use new oil manifold plate which is not cheap.

blueandred
04-05-13, 02:10 PM
Thanks stoveguyy, good idea. I'll add it to the list.

stoveguyy
04-05-13, 11:17 PM
I doubt they cleaned off motor block of oil residue so if it's filthy, that might point to a reseal job. If motor is fairly clean than its probably ok to leave it alone. U could ask mechanic if he has ever done that job.

blueandred
04-08-13, 02:46 PM
stoveguy, my mechanic owns his own shop but came from Cadillac after 23 years... He got and sent the motor back today! Said exactly what you said...lots of oil showing leaking and cross overs had issues. Never took it off the truck. Sucks not having my car but I trust him and I don't want to take chances either. With the help of everyones input, I've got my list of premptive repairs ready but I'm not going to have them done on a motor that looks like it might have issues already. Thanks.

stoveguyy
04-09-13, 10:00 AM
Maybe ur motor ain't so bad? Why not fix head gaskets? Sounds like ur mechanic is skilled.

blueandred
04-09-13, 03:31 PM
stoveguy, that was an option but the dealer wants to swap motors and pay just for the swap labor. I'm gonna pay the labor/parts to do the preventive fixes before the new one goes in. arrvied today, heading down in a few to take a look. Mechanic says night and day...

stoveguyy
04-09-13, 04:16 PM
Oh yeah. U had new used car with bad motor. Dealer is paying for used motor swap.

blueandred
04-09-13, 05:42 PM
Yup. just got back from looking the new motor over... visually it looks really clean. you can tell it wasn't cleaned up but no signs of leaks, etc. 6 month warrentee. we'll put the new water pump from the bad motor on the new one. probably gonna change the O2 sensor as well since it's against the firewall when the motor is back in. I'm gonna keep the bad motor. If nothing else I've got some expensive parts if I need them...like coil banks... mechanic is gonna give me some prices tomorrow for preventative fixes when he gets into it. The replacement includes new plugs, Amsoil and replacing the plenum so those at least are taken care of by the dealer. Keep your fingers crossed for me. should have it done by Friday.

stoveguyy
04-09-13, 05:44 PM
Did he drop cradle out bottom?

blueandred
04-09-13, 11:45 PM
yup.