Farrar's car blog

[stevedmc]

Hmm.

There's been a lot of trouble with carbed cars recently. Maybe its time to revisit K-Jet, Farrar! Look, there it is, waving to you from a box in the corner of your garage!


mmmmm k-licious.

There's been a lot of problems with all 30 year old cars recently. A bad RPM relay will cause the same problem on carbed and K-jet cars.

Edit: It might not be the RPM relay but if it works after cooling down it just might be that. Just my opinion.

[sean]

There's been a lot of problems with all 30 year old cars recently. A bad RPM relay will cause the same problem on carbed and K-jet cars.

Edit: It might not be the RPM relay but if it works after cooling down it just might be that. Just my opinion.

This is as far as the carb v K-jet tangent will go here, all others will go away.

[content22207]

Just because there is fuel in the bowl does not mean the pump is spinning at that same moment. Remember: a full bowl gives you nearly a mile (at low RPM's) worth of travel without a pump even in the vehicle.

You need to catch the car red handed. Next time it dies, immediately denergize the car (so the pump has no chance to spin), then look in the bowl. I had to do that to isolate a problem with one of my church's school buses (bowl was completely empty when the engine died, but the pump made normal noises and refilled it as soon as I re-energized the vehicle, allowing me to narrow it down to a pickup problem). If your engine dies, the pump is not spinning (because you took its electricity away), and the bowl is full of fuel at the time of dieing, then you know your problem is not fuel delivery.

Fuel starvation is a very distinctive feeling. If you want to see what it feels like, simply unplug your pump then drive until the bowl runs dry. The engine will not cut off immediately, but will limp until the very last drop of fuel for several seconds, losing more & more power and sometimes even detonating (valve clatter) in the process. It's just like running your lawn mower dry at the end of the summer, but on a larger scale.

Bill Robertson
#5939

[Farrar]

I know what fuel starvation feels like because, a while back, my fuel pump died on me when I was on the road.

The fuel pump runs; otherwise I wouldn't have made it down the block, or idled for several minutes while I tried to figure out what was going on. I don't think this is a fuel delivery problem. When I took off the oil breather cap, which I had previously cleaned with carburetor cleaner a little while ago, it was covered in goo at the bottom which looked like softened butter. I wiped it off with a papertowel and smelled it, but it didn't have a distinct smell, just kind of smoky. There was some smoke coming out the "chimney" where the oil breather cap goes into.

I looked at the top "pie plate" -- globs of that softened-butter-looking stuff were stuck to it, except they looked more brown than yellow. Like whipped peanut butter with extra oil, now that I think of it -- very shiny and soft. Same stuff was on the bottom pie plate, just not as much. There was also a little bit on the inside of the air filter. This was slightly thicker, so perhaps slightly older, than what I found on the underside of the oil breather cap.

I haven't checked the PCV valve yet... I've put off going to work today long enough.

Farrar

P.S. - Thanks, Sean!

[content22207]

Water in the crankcase. You need to get the engine up to operating temp for at least 15-20 minutes to determine whether it's condensation/humidity/etc or a head gasket leak (atmospheric moisture will boil off and not come back).

Bill Robertson
#5939

[Farrar]

Water in the crankcase. You need to get the engine up to operating temp for at least 15-20 minutes to determine whether it's condensation/humidity/etc or a head gasket leak (atmospheric moisture will boil off and not come back).

Okeydoke -- I will pull the air cleaner off and see if I can get the thing to idle that long. Even in this weather, the cooling fans do not come on when the engine has only been running for five minutes.

I will also try bypassing the fuel pump relay with a jumper (to the green wire instead of the brown one, so I don't do something stupid and drain my battery) to see if that might be the solution to Mysterious Engine Death.

If the PCV valve is blocked up again, I will be angry; I've already replaced the thing once a year ago.

Farrar

[content22207]

Was it raining when your car put you to walking? Water can play havoc with secondary ignition (for fun, Google "high voltage water bridge"). If the jackets on your plugs wires are frayed or the boots are torn (remember: leaking oil is really hard on them), voltage will jump all over a wet engine compartment rather than fire the plugs. At night you can seen it like St Elmo's Fire. Moisture inside a distributor cap will prevent the plugs from firing (this happens a lot when you wash an engine). Water inside the plug wells will cause voltage to jump directly to the block. Etc.

Bill Robertson
#5939

[Farrar]

Was it raining when your car put you to walking?

Nope; in fact, i checked to make sure the plug wells were dry, as was the area around the ignition coil.

Although it has been very wet here of late, I drove the car successfully twice (about 20 to 30 minutes of driving each trip on successive days) after completing my wire-loom project, and it hasn't rained since that last successful drive.

Farrar

[content22207]

Was your distributor cap on fire?

In all seriousness, measure resistance across the rotor button. OEM is 5K ohms, but I have one spare button that reads more than three times that. It's stupid to put a resistor in the rotor button (who listens to AM radio anymore), but that's the reality we deal with. I believe Andre in Italy straight wired his.

On the old site there was a picture of a Volvo rotor button that had melted in half (anyone still working on resurrecting those archives?).

Bill Robertson
#5939

[Farrar]

Not sure what resistance across the distributor rotor would have to do with engine temp... the engine dies just as it's getting warmed up, but prior to cooling fans coming on. Runs fine when cold. Oh well, it's worth checking anyway while I'm back there.

Thanks,
Farrar

I forgot to mention the good news: as I was back in the engine compartment trying to figure out what the hell was going on and dripping sweat everywhere, I didn't see any oil leaking from the timing cover gasket! Looks like all of that ugly silicone I gooped on top of the gap up there is working, at least temporarily.

Farrar