2.8 bogs and won't go over 58 MPH

[Jim Oaks]

Two of the plugs have some deposit on the outer electrode tgat would suggest bad valve seals.

 

[Uncle Gump]

WOT while doing a compression test really just let's each cylinder be "all it can be". Running the test with all cylinders the same is perhaps more important overall.

I think your test results just verify the bottom end is a bit tired. Does it huff any smoke?

 

[Shran]

Your first compression numbers are really low and there is really no reason why, if it was running good recently, that every cylinder would have suddenly lost a bunch of compression to the point where it doesn't run right. I am betting your timing is off or it's running really lean because of something unhappy in the carb. My old 460 had basically the same symptoms after I went through a Holley carb that I wanted to run on it (although minus the compression test) but it would backfire through the carb on the highway and had no power. I didn't really figure out what was wrong with that carb itself but I put an Edelbrock on it and it was instantly back to running great...the timing was a few degrees off though.

Had a Durasparked 2.8 years ago that was running pretty good and it just got progressively harder to start and lost power over the course of a few days. Eventually it wouldn't start at all. I got frustrated and just sold it as is, talked to the guy months later and he said (IIRC) that the drive gear on the distributor had spun and it was way out of time.

 

[Jim Oaks]

Opened the carb and checked the float. Looked good. Same position it was when I rebuilt the carb.

Rebuilt the carb, Bronco ran great, and then suddenly started to have a hard start and occassional backfire rhrough the carb issue.

I keep passing over the timing issue because this thing has a factory timing gear, not a chain, and I feel like it would be unlikely that the distributor would move, but I guess I should check it.

 

[Jim Oaks]

Distributor cap is looking pretty corroded.

 

[PetroleumJunkie412]

View attachment 94737
View attachment 94738​

Distributor cap is looking pretty corroded.

Fix ur pants

 

[Uncle Gump]

Fix ur pants

Appears to have a lot of wear in the knees.

 

[Jim Oaks]

Stop looking at my legs.

 

[Shran]

Cap looks fine, I’ve seen some that are damn near melted though the contacts that ran fine. Little sand paper will clean that corrosion up.

doubtful that the timing gears moved but I believe the distributor gear is held on by a roll pin that can shear off. Unlikely though, I guess my gut feeling is the carb is plugged up somewhere.

 

[bobbywalter]

i was leaning converter and or gear on the first post. or it was run low on water and cooked the oil and the rings are sticky.


if the exhaust is clear and its only holding 60 mph it has to be lean or there would be a black cloud behind ya at wot.


you checked every orifice in the carb? and the fuel psi running under load going down the road?

 

[bobbywalter]

of course with a durasuk box.....who knows...

 

[Jim Oaks]

I haven't checked the fuel pressure. It's a mechanical fuel pump and my experience has always been that they either work or they don't.

 

[bobbywalter]

I haven't checked the fuel pressure. It's a mechanical fuel pump and my experience has always been that they either work or they don't.

or its only working to 60 mph.



if its only putting out 1 psi there might be a supply issue.....or its sucking air too. the tank sock could be nasty or kinked.....


is the skid smashed into it?

 

[Jim Oaks]

Skid plate isn't smashed. is there an inline fuel filter besides the one at the carburetor?

I guess I need to find a way to check the fuel pressure

 

[bobbywalter]

is it sans converter?