84 fieor-- 94 N* swap (Page 19/24)
Will OCT 10, 09:08 AM
You work quick.
What pressure sensor are you using?
IIRC, there was a recall or update for Northstar oil pump relief/regulator pistons getting stuck resulting in low oil pressure.
mcfrandon OCT 10, 02:55 PM
I replaced the oil pump today and that did not help at all but worth a shot... it wasnt as difficult as i thought it would be in car. hardest part is getting that dang bolt loose.


Im using the 88 fiero oil pressure switch. Before the rebuild it was just just on the line before the red zone, 20psi i would say. Now you can see by the picture it looks to be about 10... apparently the idle minimum is 5psi, but that just seems odd that it would be less after all new bearings and new pump. I dont think it would make any sense for the cams to change the oil pressure would it? thats probably the only different thing now untested.

I read about the pressure relief valve in the oil pump but both pumps were brand new, and still make 10 psi at idle so i dont think it would have any if it were open
Will OCT 10, 08:16 PM
The Fiero dash gauge isn't exactly accurate/reliable.
Does the oil pressure climb appropriately when you bring the RPM up?
Have you verified with a mechanical gauge?

I popped a street elbow into the side of my oil filter adapter so that the pressure switch points down next to the filter instead of out through the mount bracket... *SOOOOO* much easier to work on.
mcfrandon OCT 10, 11:20 PM
Yeah it climbs with the rpm like it should. Around 2krpm cruising at 40psi. Ive drivin it quite a bit today so im not too worried at this point. Its just very annoying when the light comes on.

I havent used a mechanical gauge... i dont have one maybe i could rent one... i wonder if i should attempt to clean the sender unit. I dont have trouble getting to it.
Will OCT 13, 08:26 PM
What weight oil are you running? Synthetic or dino?
mcfrandon OCT 13, 09:05 PM
regular ol mobil 10-30. i wont be using synthetic until i can figure out why im getting a blue smokescreen on decel haha uses too much oil right now
mcfrandon OCT 14, 11:59 PM
turns out there is a crack in cylinder 2 exhaust port. im jb welding it for now and will more than likely get a new head.. eventually. theres also an odd popping noise coming from the cam cover, im not sure if that has anything to do with the different cams or not.. sound like a high spring tension popping/releasing
mcfrandon JAN 04, 11:10 PM
ok another update... I have the engine out and tore down yet again for my 3rd rod bearing replacement. The first time it went out it was the #1 bearing and i did a complete rebuild with new rings, reground crank, timing kit, oil pump... everything. Second time i lost the first bearing again. just pulled the pan and replaced the rod bearings-- crank was ok. now im on my third round... crank is ruined this time so i have another reman coming with matching bearings... the guy at the machine shop has me sold on resizing the rods. Im also thinking about ordering arp bolts but i just fee like that is overkill and as far as ive heard these engines spin up to 8500 with the stock bottom end.

Since having the cylinders honed and reringed it still seems to use a bit of oil and smokes. Im not sure how but everything is new and it still uses it. Id love to get that fixed some day. on top of that, chrfab that sold me the cams is recommending i add another quart if im going to run it up to 8500. from what i have read its a no no because the crankshaft will aerate it.

while i have it apart i decided to take the flywheel/clutch in for them to look at because it chatters like crazy. He said more than likely its the very hard friction material on the pressure plate side so looks like i will have to deal with it.
Will JAN 05, 10:45 PM
The only reason you would need to resize the rods is if you spun a rod bearing. That's it.
Also, fracture split powdered metal rods require *OVER*sized bearings and can not be resized like machined rods.

The Northstar won't rev to 8500 very long on the stock bottom end.

Overfilling the sump isn't necessary unless you're pulling more than 1g lateral.

Did you use stock pistons and rods after honing cylinders? Then your bore clearance is out of spec. That's why it uses oil.

[This message has been edited by Will (edited 01-06-2016).]

mcfrandon JAN 06, 01:35 AM
The guy at the machine shop informed me about the cracked rod setup. I have several extra rods so he is just going to spec them out and weight match them.

as far as the hone goes it was just to deglaze the walls for the new rings. little if any material was taken off. still less than 2 thou piston to wall clearance. Im probably going to get some rings from the dealer and give them a whirl