I have a 1976 F100 with a 5.8L 351W that the previous owner installed. The motor had a blown set of head gaskets, so I got a crate motor that was 0.040 over. I've bought from the company many times, and they are dead-on with their builds, and test every motor before shipping them out. So I know that the motor shouldn't be in question.

I swapped over the Edelbrock intake and 4 barrel carburetor, and installed an HEI, along with a new water pump. I also have a new balancer on the motor, new hoses, new radiator, new spark plugs, plug wires, new temperature switch and aftermarket gauges that are all showing correctly.

The problem is to get the motor to run, it seems to be happiest around 30 degrees btdc, which then means it overheats in under 10 minutes at 60 degrees outside. I removed the thermostat to make sure the pump was working, which it appears to be (I also tested the thermostat, and it works fine). I have the vacuum advance going to the timed port on the edelbrock carburetor (passenger side). I removed it from the HEI and plugged the line, then set timing at around 14 degrees. The truck bucked, hiccuped, would barely run, then stalled. I adjusted the carburetor a little and upped the idle, and when I tried to restart, had the same problem. I advanced the timing to around 22 degrees, and got it to stay running, but it would hiccup and every other minute, there would be a pop in the exhaust (guessing some unburned fuel was getting burned through a late exhaust valve).

The motor runs very nice and smooth at around 30 degrees, but with the overheating, I can't drive it. I initially put the engine at TDC on the compression stroke for the number 1 cylinder (passenger front piston). When the distributor dropped into place, it was around 3-4 degrees btdc. It wouldn't run no matter what we did, until we moved the distributor to around 30 degrees (did it by rotating, and cranking until it finally started, then checked timing to verify the 30 degrees).

Does anyone have any ideas or suggestions? I am sort of baffled on this one, and am probably missing something obvious (hopefully).

 

Did they put the cam in right. Maybe they put it one way or the other?

 

Have you tried adjusting the idle mixture with a vacuum gauge?

 

Sure sounds like its timed wrong, here is the firing order, just to make sure.
1-3-7-2-6-5-4-8.

If all is good there, I would pull the valve covers and check the cam timing with the valves. Make sure #1 is at TDC on the compression stroke and the balancer shows the same. Then go through the firing order while rolling it over and watching the valves open and close. You just have to start over and verify everything.

 

I'm not sure how the balancer keys to the crank on a Windsor but could it be clocked wrong?

 

my 2cets could they have installed a 302 cam in the 351? i know thay will work in the 351 but you have to run the spark plug wires for a 302.

 

i mean the 351 would have to run the 302 firing order .

 

it's entirely possible that it's a 302 cam. I'm going to set it back to TDC and pull the valve covers, and check to see what order the intake valves all open, and that should confirm what I have

 

When you turn it over, if the second valve to open is the cyl #5, you have a 302 cam, if the second valve to open is cyl #3, it's a 351w cam

 

Are you sure you have the correct balancer?

 

Thanks. And just to clarify, the 351w has 1-2-3-4 on the passenger side, and 5-6-7-8 on the driver's side right?

 

Yep. Passenger's side bank, starting from the front of the motor, working your way back to the flywheel/flexplate is 1234.

 

I believe so. I have to go back and double check the part number to be sure

 

I checked the balancer, and it is for a 289/302/351W:
Summit Racing part number SUM-163289
Description: Harmonic Balancer, OEM, Internal, External Balance, Nodular Iron, Natural, Ford, 289, 302, 351W

Balancer appears to be right. So either the cam that the shop used was a 302 cam, the timing chain was installed off a little bit, or something else is completely out of sync. I will probably pull the truck back into the shop this weekend and verify the intake valves to see what order they open in. After that, the engine is going to be pulled and gone through.

 

if you have a spare distributor to swap out to see if it makes any difference i would try that. my 306 i built i put a points one in it and could not get that thing to run so i put on duraspark II and ran great. i still have timing issues on mine. my will start easy when i turn the timing one way but overheat fast and get really choppy after 2000 rpm but if i time it within 6 degrees it will hardly start after warmed up(like battery is dead) now ive got it starting everytime but popping a lot. i dont know where i have it set exactly i took my timing light home. this is the first windsor ive done and sounds like we have a similar problem. im beginning to thing about cam timing instead of ignition timing. i bought the summit gear drive and the crank gear can be set at different degrees and i think i might try that. one thing i didnt do was degree my cam.

it may help to set the timing where you want it then re-stab the dizzy another tooth