bobcat 732 engine problem

chrisdvorak · Aug 16, 2014

okay I got the machine cranking again. but still no start. did another compression test and found this
no 1- 30psi
no 2 -90psi
no 3-120psi
no 4-120psi
I would think if worn piston rings were the problem the numbers would be lower across the board? also with 2 good cylinders shouldn't it at least try to start? plugs are wet and I have blue spark. when it was running briefly it was not smoking like it would if the rings were worn.
also I adjusted the valves by the rule of 9, is there any different way I should adjust them?

-thanks

chrisdvorak · Aug 17, 2014

anyone?

chrisdvorak · Aug 22, 2014

Okay so I've found out some new details, after putting raw fuel into the spark plug holes I got it to start and run for a few seconds so this confirms a carb problem, so I rebuilt the carb. And thoroughly cleaned it (wasn't very dirty to begin with) and still no change. Engine now has plenty of vacuum. Previous owner updated the fuel pump to a small electric one, is it possible that this is creating too much pressure for the carb?

DJ54 · Aug 22, 2014

I did a quick Google search for an '80 fiesta 1.6L fuel pump pressure, and came up with this as a match for a universal fuel pump for one.

80 1980 Ford Fiesta Electric Fuel Pump 1.6L 4 Cyl Beck Arnley
Sale Price:
$59.23
Quantity:

(34) In Stock
Product SKU: 152-0576
Product Note: Electric Fuel Pump -- UNIVERSAL TYPE; Universal Type 2-1/2 To 4-1/2 Psi Rating

If the PO used a pump like a Mr. Gasket, they may have gotten the higher pressure one 4-7 psi. They do make a lower pressure one 2-3.5 psi.

I guess you could make sure the carb. bowl is full, then relieve the pressure off the line, and see if it would start.

chrisdvorak · Aug 23, 2014

Thanks DJ54, I tried filling the carb bowl and starting it with no fuel pressure and it still would not start. I looked Into my fuel pump and it states only 1.5 - 4 psi so I guess it's not a fuel pressure problem. I am out of ideas for the carb except for just replacing it with a new one but I really don't want to spend 300$+ only to have the same problem in the end.
By the way it's a zenith model 68 updraft.
If anyone else has any other ideas please chime in!

DJ54 · Aug 23, 2014

Spark, fuel (wet plugs) and air, it ought to at least pop. Almost sounds like more of a timing issue.

I'm not sure what 4 cyl. engine was used in Ford Rangers in the early 80's, but the one they gave me for a work truck over a period of a year's time got pretty week on hills, like there was no spark advance. Finally got one of our mechanics ( a real one) that found the rivet that holds the advance plate had sheared off. He put a new one in, and it ran like a striped ape after that.

chrisdvorak · Aug 23, 2014

I have chased a timing problem already to no avail. I advanced and retarded the timing with no change right now I just need to get the engine running and it should run without the vacuum advance hooked up. Once it's running I can fine tune it.

DJ54 · Aug 24, 2014

Is it possible it's getting too much fuel, like over choking and engine, and a flooded condition..?? Plugs gapped properly..??

Your one quote "Set the points @ 12º BTDC" kinda' threw me. I'll assume just a misquote, and points were set to proper gap, and timing set to 12º BTDC. Not sure what the gap would be on that engine, but the older fords IIRC were right at .019". A buddy of mine years ago used a business card as a feeler's gauge, LOL...

chrisdvorak · Aug 24, 2014

Yes it was a misquote. Points are set to .025 as per manual. Ignition timing set at 12BTDC. Today I removed the spark plugs and with each cyl at TDC I used compressed air to clean and dry each piston, did the same to the plugs to ensure everything was bone dry and reinstalled them. Then I set full choke and cranked the engine for a good 20 seconds ( carb bowl had fuel in it) and the plugs were still bone DRY. Has to be a blockage in the carb somewhere I would think but I have cleaned and inspected every part of it countless times and everything is clean as a whistle??