Sluggish acceleration 1985 Colony Park

If I can remember that far back, there were two things wrong with those engines.

At around 100K miles, the valve guide seals were so hard that they started to crack and find their way into the oil pan. Co-incidentally, oil leaked down the valve stems and started coking up the underside of the valves and usually the rear cylinders started to oil foul.

At the same mileage, the timing chain was usually stretched, altering the timing. That, coupled with an aluminum cam gear with bonded plastic teeth, was an accident waiting for a heavy load or backfire to sheer the teeth off the gear.

It gets even better! The cracked valve guide seals find their way to the bottom end and get sucked past the oil pump screen into the pump. The pump locks up and sheers the gear off the distributor and usually takes the plastic gear teeth with it.

Preventative maintenance for such a Ford with a 302 or 351W was to repair all of the above before it happened, as it was cheaper. Once the pump locks up you have to pull the oil pan which is a royal bitch without pulling the engine.

All of these things affect the performance of the car.

 

Holy cow, the bullet proof 302 coming apart at the seams? Is this limited to a few years? Wondering about my 91 CP.

mike

 

Yes and no. I inherited my stepdad's 90 F150 with a 302. It had the valve seal problem and was fouling plugs. I pulled it down to change the chain and gears, but it had steel gears. Don't know if that's because it was a truck or if they changed the cars too. The chain was still stretched.

I kept it for several years as a backup vehicle, but sold it to buy my wagon.

 

I've been under the hood this weekend cleaning, testing, etc. The vacuum diaphragm that controls the fast idle lever is shot. I've been all my local auto parts stores and combed the internet today looking but can't find a replacement. Do any of ya'll know where go to look for this?

 

Good question. Sometimes you can get lucky on e-bay. Cant remember if it crosses with the one used on the motocraft 2bbl carb.

 

Old Fox, I have put a LOT more than 100,000 miles on Windsor engines of from 79 through 89 as has my brother. The only time we have had to do a timing chain was on one of the 86 351s, and it had roughly 400,000 miles on it. We've never had valve seal or oil burning problems with any of them.

 

When I rebuilt my fuel charging assembly (the carb-looking item), I bought my rebuild kit from Car Quest, but that was 2003. And just so I'm clear, is yours an '83 or an '84/85? Makes a big difference, as '83 was EEC 3 and '84/85 was EEC 4.