Turbo7MN

Hey guys, over the last couple weeks me and a buddy have been swapping out my motor (86 N/A) with a blown coolant seal for a reman (also S4 N/A) he found at the junkyard he works at. The plan was to put this engine in so I could still drive the car until I rebuild the other one. As a little background info I did not personally see the engine run before it came out of the original car, which was complelely drained of fluids and hacked up. The motor had a blue reman tag on the front though and when we were working with it, there was no doubt it was rebuilt. It also turned over fine by hand with a strong chug on every chamber and the apex seals looked good when we checked them out through the exhaust ports.

Okay, fast forward to today. We finally finished hooking everything up using my intake manifold, injectors, rats nest, pretty much everything off my motor except the alternator because we already knew my car ran fine before we pulled it. It fired up after a couple cranks but was running very rough. At 3K RPM the driver's seat felt like a massage chair. Maybe rough isn't the right word, it's not like it was missing a lot, it just vibrated more than usual. If you let it try and idle on its own it would die. We started it two or three times trying various things to keep it running but eventually no matter how hard you tried it would always die. I didn't get a chance to drive it to see if it had any power. One thing I noticed when it was running was it sounded a lot different than it used to. I have a custom true dual exhaust that I'm pretty familiar with how it sounds, this time it was a lot lower in pitch. What really seemed odd was when it was revved, especially in the higher RPMs, it had a definite "brap brap" sound to it that I've never heard from my car before. Part of me is almost thinking this thing might be bridgeported because of that (I'd have no way of knowing for sure) but it died at times other than when I tried to let it idle so it's probably ignorant speculation at this point.

Anyway, as it sits right now it will not start again. It seems like it will fire once or twice and then crap out, but it will not start at all now. This kind of sounds like a vacuum leak, but why would I have been able to get it started before and now nothing?

The plugs were brand new when I put them in. When I checked them there was a slight black deposit on all of them with the largest of the deposits being on the front leading plug. The deposits seem to be concentrated around 1/4 of the plug.

Before anyone posts "search" or "download an FSM" I have searched for a while and have not found anyone with the same circumstances I am dealing with and I have a paper copy of the '86 FSM. I'm hoping someone here can shed some light on what I should be looking for tomorrow and perhaps if any of this sounds familiar to anyone.

Thanks in advance. Hopefully I can have this thing going by the end of the week.

-Darren

Eva001Ikari

iTrader: (7)

well when i bought my true dual exaust i had to disconnect my intake, just the hose and the filter in order to install the headers. Anyway, when i put everything back together, i forgot to reconnect the air flow sensor.... i think its the air flow sensor, the one inside ur intake pipe, that little plug on ur intake. Anyway before i plugged it back in my car would start then idle for like 3 seconds then just die, i could floor it and it would get to like 2.5k then die. Eventually it stopped running all together. Anyway i got out of the car and realized i didnt plug it back in so i did, and it ran fine after that......just a thought but you might want to check.

micah

Sure you had the plug wires wired up correctly? Timing off? Might need to re-stab the CAS.

Definitely check for vacuum leaks and such, but that wouldn't make it run rough like you are describing.. not typically anyways.

How old is the gas?

phoenix7

I'm with Micaheli. Have you made SURE you have no vaccuum leaks? As mentioned above, make sure everything is connected properly.

Post a vid or sound clip to see if it helps?

Turbo7MN

Yeah, I actually specifically remember checking that the AFM was hooked up before I tried starting it.

I'm not 100% that there's no vacuum leaks. We only replaced ones that were in questionablle condition, but like I said this is the same manifold I've had for nearly 4 years that the old motor ran fine with.

We're pretty sure we had the plug wires on right, My buddy decided to switch them to see if it helped and it didn't. Timing seems like a logical guess. I'll check it out tonight.

Thanks for the input guys.

-Darren

Turbo7MN

Okay, the AFM was hooked up right. I made sure the spark wires were right. I did find one hose not on all the way, but it was just the one that connects to the oil filler neck. We made sure the motor was getting spark, didn't check timing though. The gas is only about a month old, if that.

But we did get it started again. We ran a can of seafoam through it (from the brake booster line) and now it will at least idle on its own. I drove it a short distance too. No power whatsoever. Nothing is quite as fun as driving a powerless car at low speeds with no power steering (its an 86 base) with a brand new street/strip clutch.

Anyway, the vibration, the lack of power, pretty much everything seems to point to it running on one rotor. We checked the seals through the exhaust ports before we dropped it in and they all looked fine and there was definite compression on every chamber so this seems kind of odd to me.

Do you guys think that a seal could have just popped out the first time I cranked it, or is there maybe some other underlying cause here and I still might have a good engine? I don't have access to a rotary compression tester at the moment but I'll check it "by ear" tomorrow or Wednesday when I have a chance to work on it again.

-Darrem