There's a lot of paranoia on the Cadillac forums about reusing old main bolts because of stretch 'n' snap. I suppose I could just measure them to be sure. You didn't have any issues with your main bolts, did you Will? I mean, you've been in there at least twice now, right?
Correct... I don't have any qualms about re-using main bolts and neither does CHRFab. Follow the torque procedure *correctly* and you'll be fine. Main bolts are *NOT* torque to yield.
Just like any other fasterners, there can be problems if you look at a large enough sample set. Out of 1000 engines, there are 20,000 main bolts, all made by the lowest bidder. Will every last one of them take multiple torque cycles? What if we bump out to 10,000 engines and 200,000 main bolts...?
That's the paranoia of forums... you have no idea how large your sample set is. So it happened to one guy... is the failure rate 1 : 2,000 or 1 : 200,000?
I just wanted to make a quick comment on people saying that the northstar build is rediculously expensive to do. Im pretty far into my swap now and I dont see many more purchases in the future and im only into it for roughly $1000. Thats including buying an entire 99 deville( which I scrapped and got half my money back), megasquirt 2, mshift trans controller, ns300l inserts for head bolts, head gaskets, all pipes and collectors for 180 degree headers, and the rest of the exhaust. Yes it can be expensive but it doesnt have to be.
With the possible exception of the front cover seal, all the seals in the engine should be replaced when opened. That makes it a $50 operation to take the valve covers off. So if you use Cometic gaskets that don't take the stock torque procedure, ARP studs torqued to a particular number, and then pull the valve covers to re-torque the studs after a dozen heat cycles... it all adds up.
As mentioned, $90 for the oil plate, a few more the the oil pan seal, case half seals, chain guides... etc. Bearings are 10x as expensive as Chevy bearings, for example.
It's not a BMW as far as costs go, but it's more expensive than an LS or SBC.
I dont have any real experience with the ls so I cant say much for that motor. I agree the northstar is more expensive than a sbc, they were used for a very long time and parts are everywhere for them. That being said I beleive you get alot more from a northstar than a sbc, they are quite a bit heavier and the money you would have to spend on it to get the same power as the northstar would bring the cost of the swap closer to the same.
Im not gonna say you are wrong about valve cover seals neading to be replaced everytime the covers are removed, you definitely know more about the northstar than I do. I have worked on alot of engines with similiar seals, on vehicles I owned or friends vehicles, and we have reused them without any leaking issues.
The bearings are expensive for these motors. I was fortunate that mine were in excellent shape (at only 113000 or so miles I would expect them to be)
Do any of you have issues with oil starvation when making hard right handers?
Allen Cline told me that they tested the engine to angles of up to 45 degrees on the dyno. It should be fine up to 1 g lateral *AS LONG AS* the sump is COMPLETELY full with the factory 7 quart fill.
If you're pulling more than that (quite possible on modern high performance street rubber or race tires) then you may have to overfill the sump to compensate.
Bearing surfaces look great and it ran just fine before I tore it down for the reseal. The leak probably wasn't as catastrophic as I made it out to be, but I really would prefer to have a motor that doesn't leave it's mark everywhere. I found the busted wire in my oil sender harness causing me to think the motor lost all oil pressure. It had ~70# cold pressure before I tore it down. I've got all of the '96+ oil manifold and supporting parts ($200+ later), so I'm ready to put it back together. I'm pretty confident that just reassembling and resealing according to the GM TSB will be fine. I've got two tubes of their RTV and a sturdy gun with which to apply it. Any other tips for reassembly? Should I be replacing the front timing cover or seal, or anything up there? Trying to finally get this car on the road this spring.
[This message has been edited by 1986 Fiero GT (edited 10-12-2015).]
McMaster-Carr has 50ml tubes of the right anaerobic sealant (Loctite 518?) that will do multiple engines. It's better in thin applications than RTV. Don't forget to clean the surfaces with brake cleaner and at least 90% isopropyl alcohol in order to make sure it's clean enough for the adhesive to work.
Your primary chain (from the crank to the intermediate sprocket) tensioner looks like it desperately needs to be replaced.
McMaster-Carr has 50ml tubes of the right anaerobic sealant (Loctite 518?) that will do multiple engines. It's better in thin applications than RTV. Don't forget to clean the surfaces with brake cleaner and at least 90% isopropyl alcohol in order to make sure it's clean enough for the adhesive to work.
Are you saying that the GM RTV, specified in the TSB, is not the sealant that I should use? I've already got the two tubes I need; won't it work?
I scrubbed with brake cleaner. I was planning to wipe everything down with a 90% isopropyl-soaked lint free towel just before assembly. How clean does it have to be? Is baked-on oil varnish okay? Down in the channels, some of that wouldn't come off even with light persuasion from a towel-wrapped screwdriver. Didn't want to make a mess of the channels, so I left it as good as I could get it. The actual flat surfaces, I scrubbed perfectly clean.
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Originally posted by Will:
Your primary chain (from the crank to the intermediate sprocket) tensioner looks like it desperately needs to be replaced.
Wonderful. Should I just do that one tensioner? I mean...it looks like it's not too big of a deal to completely replace all of the timing wearables based on how far the motor is already torn down. Just pull the valve covers, pretty much. Found a kit on FleaBay for like $170. No brand name, but the parts are identical to the AC Delco ones at RockAuto. The single tensioner is only like $20, though. I'll have to take a good look at all of them this weekend. Definitely worth it to me to just do it all now if required.
Oh, and the front cover/seal and front main seal. Should these be replaced?
[This message has been edited by 1986 Fiero GT (edited 10-15-2015).]
Are you saying that the GM RTV, specified in the TSB, is not the sealant that I should use? I've already got the two tubes I need; won't it work?
I scrubbed with brake cleaner. I was planning to wipe everything down with a 90% isopropyl-soaked lint free towel just before assembly. How clean does it have to be? Is baked-on oil varnish okay? Down in the channels, some of that wouldn't come off even with light persuasion from a towel-wrapped screwdriver. Didn't want to make a mess of the channels, so I left it as good as I could get it. The actual flat surfaces, I scrubbed perfectly clean.
The GM material *IS* Loctite 518. IIRC, the GM tubes are 5ml. In order to be SURE your case joint doesn't leak, you'll want to run thin beads of the sealant both inboard and outboard of the stock linear seal. You'll want to use the linear seal also, because it gets adhered to both the rear main seal and the front cover gasket with dabs of RTV. It sounds like you have the surfaces clean enough.
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Originally posted by 1986 Fiero GT: Wonderful. Should I just do that one tensioner? I mean...it looks like it's not too big of a deal to completely replace all of the timing wearables based on how far the motor is already torn down. Just pull the valve covers, pretty much. Found a kit on FleaBay for like $170. No brand name, but the parts are identical to the AC Delco ones at RockAuto. The single tensioner is only like $20, though. I'll have to take a good look at all of them this weekend. Definitely worth it to me to just do it all now if required.
Oh, and the front cover/seal and front main seal. Should these be replaced?
Check your tensioner shoes and chain guides for wear. I've had a front main seal not be a tight enough press fit into the front cover and had to replace it for that reason. As long as it is in good condition and the sealing surface of your balancer isn't grooved, it should be fine to re use the front main seal. I'm not so sure about the front cover gasket, but it's not that hard to remove in the car.
[This message has been edited by Will (edited 10-18-2015).]
Oh, that's good to know about the sealant. I put it back together yesterday. I followed the TSB for the main bolts, 15 ft/lb then 65 degrees. The bolts were tight, but it seems that they were much tighter when trying to remove. Maybe it's just me. I've never reassembled one of these motors before.
Good to know about the front seal. I'll just clean everything up and put it back together. If it leaks, you're right; it's not tough to replace in the car. I've got a puller kit now, so no big.
Would you recommend replacing the cam pulleys as well? Some websites recommend replacing all of the pulleys when replacing the timing components in a GM chain drive motor. The kit I'm looking at includes the intermediate pulley, but no crank pulley or cam pulleys. RockAuto lists cam pulleys for $25-$35 or so apiece. As you well know; there are four and then the $25 crank pulley. Are the pulleys absolutely necessary?
I need to get a GM service manual for a car with a Northstar so I can read all of the factory procedures.
I've mixed, matched and reused chains and sprockets. I can't see how the sprockets could possibly be worn, as there's never any relative motion of steel on steel during the operation of the chain.
