new 351w timing help

[chavis77]

just put my rebuilt 351w in having problem timing it had to use 302 firing order
it starts and runs at 45 degree of timing when i turn it back to 10 to 14 it doesn't run stalls hard to start just having a hard time getting it timed and tuned my vacuum is in the low 20's does drop when i retard it
when i hook up vacuum adv to timed vac it runs rough when u give it gas

 

[Viperwolf1]

Did you use the 302 order to make it run or does it have a 302 cam in it?

Best thing to do is pull the #1 plug and verify TDC is correct at the timing marks. Some balancers are marked on different sides of the timing cover.

 

[chavis77]

I used 302 firing order to make it run tried everything to make it run with 351w even 180 off still would run just pop threw carb no mater what so used 302 fired off ran smooth so must have 302 cam??? machine shop did'nt tell me what cam other then a RV cam my balancer is a summit but it did line up with pointer on tdc

 

[Viperwolf1]

used 302 fired off ran smooth so must have 302 cam???

Maybe. If you can verify the cam order it would help get everything else sorted out. I'd either pull a valve cover and check the valve order while turning the motor by hand or pull a couple more plugs and feel for compression on #3 and #5. One of those should be compressing 90 crankshaft degrees after #1. That will tell you what the cam order is.

 

[chavis77]

ok i'll make sure the firing orders right go from there it shoul'nt run good 45 adv

 

[66fora69er]

Couple of dumb questions/suggestions: your plugs are set at 1-3-7-2-6-5-4-8 CCW right? You are putting the engine at TDC and then stabbing the dizzy so that the stator is pointing to #1 plug right? I had some weird timing issues and discovered I was way off on the dizzy install. trace your plug wires to the locations and make sure they are in the right spot. I know you've probably checked all that but its worth looking at again. SBFtech.com is a good source for info too. Good luck

 

[rsharpnm]

I like the idea of double-checking distributor position and firing order wires. If still not working, pull valve covers and note the progression like Viper says.

RANT WARNING: I hate it when a camshaft is described as an "RV" cam. What does this mean? Nothing? Less than nothing? I had a motorhead friend once who said, "RV cams make torque down low." Well, that's wonderful... what are the specs? Lift, duration, etc? Sigh.... and to hear a *mechanic* say it. I weep for wrench-turners everywhere. /RANT

 

[broncnaz]

If your balacner doesnt line up with the timing marks at TDC then thats a lot of your issue might want to get some timing tape get #1 up to TDC and install the tape. Or make a new pointer to match your new TDC. Either the balacner is wrong or the timing gear set is way off. I'd bet balancer. Id say if you were getting vacuum readings in the 20's then you had it timed good at that point. Which would also lead me to believe it was wired correctly.

 

[76 bronco J]

RANT WARNING: I hate it when a camshaft is described as an "RV" cam. What does this mean? Nothing? Less than nothing? I had a motorhead friend once who said, "RV cams make torque down low." Well, that's wonderful... what are the specs? Lift, duration, etc? Sigh.... and to hear a *mechanic* say it. I weep for wrench-turners everywhere. /RANT

>>> too funny..... I also can't stand it when somebody starts yappin' about a RV cam................

 

[chavis77]

OK positive its a 302 firing order called on it i checked checked firing order way to many times pulled plug and valve cover bumped it over till blowed finger off balancer reads tdc intake last valve that moved so pos tdc rotor pointing at #1 did that 5 times even tried 180 off nothing ok looking at the motor from front of bronco firing order goes to the left right I gotta be missing something

 

[bax]

OK do this. Your finger got blown out of the hole and you checked the timing mark and the dist is pointing at the #1 plug wire. please check if the piston is TDC. I mean all the way up. Put a screwdriver in the plug hole and hand crank it to tdc. Then take a look at what you have. Is your timing mark even close? If it is adjust the dist rotor/ cap to point at #1 wire. If not you may be one tooth off on the cam shaft gear set up.

 

[chavis77]

ok I'll try that tomorrow its a new motor only had one position for timing gear
but that doesn't make it right so what i thank is tdc may not be b/c it not all the way up right bax your a smart man I'll try that

 

[chavis77]

distributors new

 

[chavis77]

ok i thank I maybe 8 degrees of on my timing gear b/c it acts like it jumped timing so if that the problem what would the fix be I have new timing chain set

It should'nt be this hard to time a new motor

 

[bax]

take the front cover back off and reposition the gear set. Put it back together.

 

[Viperwolf1]

8 degrees would be about 1 tooth off on the cam gear.

 

[73azbronco]

was your cam chain installed straight up or was the cam advanced or retarded?

 

[DirtDonk]

I think he said it was a single position only gear set. That right Chavis?

One thing I've been worrying about here though, is that all this bumping and grinding and messing around is not doing your new cam any good at all. Is it a roller cam, or standard flat-teppet? if a flat-tappet, you could be damaging your cam with all of this spinning.
Next time you get it running even half-way decently (if you can), just keep it revved up to 2500 for at least 20 minutes. Even better would be 30.
Also, did you add a zinc additive for the break-in? Or are you running a zinc-rich break-in oil?

Just a few things to think about (among all the other things you're dealing with!) during all this "fun".

Paul

 

[bax]

single position gear set still does not mean the gears are in the correct position when the chain got installed.

 

[chavis77]

ok guys timing chain lined up dot to dot but dowel pin seem to be off a little very little will match it up tomorrow with a new set (my spare) talked to the machine shop to day and he's coming over this weekend to time it or figure out whats up
ok now could a distributor cause all this its new but it is a pro comp hei knock off 50$ china made junk could the mechanical advance be adv to soon ????