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A groundhog took me out

Hi Everyone,

I was wondering if anyone could offer some insight into a problem I am having with my 1986 F250 W/7.5 450. The engine may be from a 1974.

I keep my F250 on my wildlife reserve during the summer. I kept it up on my driveway but one day I came down to connect to connect the coil wire up to start it and when I popped the hood open there was a groundhog in it starring me dead in the eyes. After 50 pokes with a stick it finally took off. The groundhog ate my K&N air filter so I replaced it. I then went for a drive to get some mulch. I then parked the truck about 1200 feet away under a pavalion. I went to start it two weeks later and it wouldnt start. I sprayed some ether into the carb and before I got out of the engine bay I noticed there was gas all over the engine. A groundhog had come in and ate through the gas lines. Two weeks later while replacing the gas line I noticed that all my spark plug wires were bitten through. Not chewed up, but just one bite each to cut them off. In any event I went to get new plug wires and found that my distributor had a different type of connector. The new plugs connected to raised posts, while my old plugs slide down into the distributor cap. So I went and got a new cap and rotor and they were about 25% bigger than what I had. I went back again to the auto parts store with my original cap and rotor in hand and a guy said to try one for a 74. They were a match.

I went back and changed out the rotor, the cap, and the plugs but the book I had was for a 1986 F250 and who knows what engine I have. I used the firing order and cylinder layout from the book that I had. I couldnt tell where each plug wire went too because the wire was chewed. Now when I start it it starts ok but I can hear misfires out of my exhaust if I try to drive. When the engine is cold it kinda loobs unless I give it some gas. If I have the car in park and floor it the engine revs fine. As soon as I put it in drive and try to drive up a hill it backfires and dies. I can run low speed over my pastures with a little "pop" noise coming out of my exhaust every few seconds.

Any ideas? Think it's just one cylinder not firing? I tossed my old cap and rotor so I cant stick them back on. Anyone know how to tell what year this engine is? There's no code on the cylinder covers...

Thanks,

Sam

Reply to
usshopkins
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The firing order is normally stamped or cast into the intake manifold.

You can line up the timing mark on the flywheel to get # 1 cylinder. To do this you need to take out the spark plug on #1 and put your finger in the hole as you use a wrench to turn the crank. As the timing mark on the crank comes up to the mark on the case, you will feel compression under your finger. If you feel no compression, you would be on the exhaust stroke and you need to turn the crank one more rotation to get the compression stroke.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >
Reply to
Mike Romain

Hi, Sam, sounds like you're already close to correct, so start where you are. IIRC, Fords along 1974 year-models used 2 firing orders: (A)

1-3-7-2-6-5-4-8 and (B) 1-5-4-2-6-3-7-8. Assume they are numbered as follows: Driver's side reading 1,2,3,4 from front to back; and passenger's side reading 5,6,7,8 front to back. Look at what you have done and it should come close to one of these 2 firing orders. Using the one which is closest, swap what sounds like 2 wires(you may have 4 mixed up, but don't think so) to make it correlate with this selected firing order. Should run good--at least as good as it did before feeding the pigs!. HTH, and good luck. sdlomi2(Sam, also!)
Reply to
sdlomi2

OK I found out that the engine is a 1978 460. Does anyone know the cylinder layout on the engine block if I am looking at the engine from the front of the truck and also does anyone know the cylinder layout of the distributor?

snipped-for-privacy@yahoo.com wrote:

Reply to
usshopkins

The distributor layout can be anything the last person that worked on it set or clocked. The only way to find out for sure where #1 is on the cap is to pull the plug on #1 (front drivers side) and check for compression when the timing mark comes up to TDC as I mentioned.

Sdlomi2 or Sam posted the cylinder orders for you with some possible firing orders and 'your' firing order should be cast into the intake manifold.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >
Reply to
Mike Romain

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