Fresh engine won't start.

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Fresh engine won't start.

October 05, 2009, 03:44:27 PM

Ok, I've been trying to figure this out for a while. I dropped a rebuilt (not professional) motor in the Bird, and it won't fire up. Turns over, spark fires, timing is set to 10 BDC (stock, according to my Brother's mustang manual), fuel is getting into the cylinders, pressure is good, but no bang. Only time I hear anything is when I try it a second time a couple minutes later, but only very softly.

Ask ideas/questions?

Fresh engine won't start.

Reply #1 – October 05, 2009, 03:50:24 PM

Verify timing. As in go back and triple-check your ignition timing.

Also, verify your fuel pressure (is the car EFI or carb?).

Fresh engine won't start.

Reply #2 – October 05, 2009, 04:02:12 PM

Firing order? Distributor in correctly? Compression test?

Fresh engine won't start.

Reply #3 – October 05, 2009, 04:37:33 PM

I'll do timing and pressure again. It's EFI. Brand new pump. Was reading 40 psi (I think) at priming.

Firing order for a 351W is the same as an H.O., right? Distributor should be in right. Haven't ran a compression test yet, but considering it won't idle and warm up, I don't really know what numbers I should be looking for.

Fresh engine won't start.

Reply #4 – October 05, 2009, 05:00:54 PM

Remember,reverse rotation on the firing order.

Fresh engine won't start.

Reply #5 – October 05, 2009, 05:01:33 PM

If you haven't had it running yet, how do you know where the timing is set? Who rebuilt the motor and what went into it? Roller cam or flat tappet cam? Is the cam in correctly? Definitely run a compression test...if the cam was installed incorrectly, you'll find out quickly during a compression test.

When I dropped a 351 in my 'Bird I had the timing set to 6* BTDC (according to the timing pointer) car started up and ran very poorly and quite lazy during break-in. Once I put a timing light on it @ idle, I found it to be 8* retarded instead of 6* advanced.

Good luck,
Don

Fresh engine won't start.

Reply #6 – October 05, 2009, 05:59:21 PM

I did it with the timing light just cranking it. Thought that would get it close enough.

Engine is a basic rebuild. My brother and I did most of the work. Some of the tricker parts we left to the machine shop. It's a flat tappet with E7 heads, new stock cam and pistons, and a GT40 upper. My brother installed the cam, and said he lined up the marks.

Vinnie, reverse rotation? Are you talking about this:
"302 non HO uses the 1-5-4-2-6-3-7-8
302 HO and 351 use the 1-3-7-2-6-5-4-8"
I was using the HO order, but I'll double check.

Fresh engine won't start.

Reply #7 – October 05, 2009, 09:50:43 PM

So you are using a stock 302 tbird cam and have E7 heads bolted on and have the wires set to a 351w or 5.0L HO firing order?

If that is the case you need the non HO firing order for the plug wires.

Fresh engine won't start.

Reply #8 – October 05, 2009, 09:53:05 PM

No, sorry, stock 351W truck cam. I bought a rebuild kit.

Fresh engine won't start.

Reply #9 – October 05, 2009, 11:42:01 PM

does it do ANYTHING? pop out the intake? pop out the exhaust?

pull the oil cap off and have someone try to start it. is there pressure coming out the valve cover? if so you may not have any compression.

Fresh engine won't start.

Reply #10 – October 06, 2009, 02:39:10 PM

I am assuming EFI.

I believe Vinny was referring to the fact that the Ford distributor rotates counter clockwise.

I am surprised no one has said it yet. Any codes?
So if you pull a sparkplug, they are wet with fuel after cranking (have fuel)?
Do you smell fuel after cranking (perhaps too fat)?

Try cranking while holding the throttle wide open. This should tell the ECM to assume the engine is flooded. If it fires and dies right away, your probably running to fat. Check vac lines, particularly the one going to the MAP.

Have you checked to see if your timing is 180* out? (Pull plug 1, put thumb over hole, bump over engine till you get a good puff. The Distributor should be pointing at or near plug 1.) If its pointing 180* out. you can move the plug wires on top of the cap or re-stab the distributor.

Here is a test I use to see if the computer and ignition module is working properly.
Remove the distributor tiedown. Pull the distributor up until the gear clears the cam. Make sure the body of the distributor is still in good contact with the block (or run separate ground wire).

Remove the cap and stick an old sparkplug in the lead coming from the coil and ground the base somewhere on the frame.

Turn the ignition on to run and slowly rotate the distributor button counterclockwise. You should hear an injector fire ("Fizzzzt") and then the plug should fire ("snap"). If this fails, troubleshoot fuses, wiring, Ignition module, and computer.

Fresh engine won't start.

Reply #11 – October 06, 2009, 03:59:23 PM

Small pops out of the exhaust, but very light, and only after it was tried once.

Only code I'm pulling now is the 2nd fuel pump monitor, but I haven't ran that line for the Mass Air conversion.

Spark plugs do get wet and I do smell fuel after a bit, but since none is burning, I kinda expect that. Cracking the throttle does nothing either.

I did do a 180 out test. I also installed the distributor with the valve covers off, so I could tell if the valves were closed and I was at TDC. The ignition module prevents me from turning it completely around because it hits the intake.

I'll try that distributor test.

Fresh engine won't start.

Reply #12 – October 06, 2009, 04:01:38 PM

I just went through this bs with my mass air conversion. What MAF are you using?

Fresh engine won't start.

Reply #13 – November 09, 2009, 07:14:55 PM

Sorry, got caught up in school. Got back last weekend, and got to check a few things:
Checked the timing again, but still nothing. Next time, I'm going to pull off the valve cover.
MAF is a Mustang CW31 reprogrammed to use #24 injectors. Tried it with 19's too, but same thing.
Fuel pressure gets up to 40 psi, but it does it kinda slow. Not a crawl, but noticeable.
Here is the kicker: No compression. Nada. Brother said the needle didn't even try to move. I'm guessing 1 of 2 things: Cam is in wrong, which is a pain, but better than #2, the piston rings are lined up.

Fresh engine won't start.

Reply #14 – November 10, 2009, 03:55:16 AM

I would think you would still have some compression with the rings lined up. If you have no compression, I would bet its time to pull it all out and figure out where its messed up.

Pull off your timing chain cover, and make sure everything is lined up. Pull out a spark plug and make sure you have compression and the piston is moving to TDC when the valves open and close. I would swap out to a H.O. cam. The truck cam is basically the same as an old tbird cam. It would be easy to convert over to roller rockers while you have it apart too.