62 Ford 961D

[TractorDad3]

Greetings, I have a long road ahead but I am considering a rebuild for a 1962 172D engine. Approximately 5000 hours. It ran at idle barely before catching shut off on the throttle shutoff, then went to full bore if you touches the throttle (fuel delivery problems, pump to be rebuilt not by me.) Unfortunately Ive only heard it run to get it on a trailer and off, but no other issues could be noted.

Upon removal of the exhaust and intake manifolds, I noticed the exhaust ports for cylinders 2, 3 and 4 in the head (and manifold) were excessively coated with carbon, such that the passages for exhaust are much smaller than they should be.

What does this mean? What causes this in these three cylinders and not as much in 1, and what other problems could this have caused? I figure I need to get it cleaned out. Thank you for your thoughts!

 

[shaun wallace]

I would get pump fixed as said. Clean carbon out of ports and find something to work it hard for a day or so, then see if really needs a major overhaul. I have not seen proofmeter get that many hrs on them on 100 series before they quit.

 

[TractorDad3]

Thank you for your comments Shaun. From notes in the I&T of the PO, it was overhauled with bearings and rings at 4199 hrs. Looks like oil has been changed every year up until 4900 hours/April 2019, so a fluid change is clearly in order as well.
Any suggestions on removing the buildup? Carb cleaner? Thinner? Bit nervous about that crap falling down into the cylinder.
SN: 118838 can still be found where it is supposed to be

 

[KCM]

As for the pump, sounds like the plastic flex ring on the governor weight cage has failed. This will cause the throttle response you mentioned, and is a common failure on old Roosamaster pumps. If you do a search on the web for Roosamaster weight cage flex ring and EID you will find a lot of information, including repair videos. The fix is to take the lower end of the pump apart and replace the flex ring, or replace the weight cage with a solid one that eliminates the flex ring and the problem forever. Pump kits and the cage are available online if you feel you are up to doing it yourself. Roosamaster repair manual is available online (see link).

Maybe the failing flex ring caused excess fuel delivery to the engine, and the carbon you see. Would definitely get the pump fixed first before assuming the worst with the engine.
Stanadyne Roosamaster DB Injection Pump Repair Manual