I picked up this van last week in Seattle, it stuttered something shocking when taking off (flat spot) but went fairly well once moving. Until it reached a slight uphill slope and then it was gutless.

A couple of refuels it improved and much of the time it can cruise quite well at 65mph. Until a hill is reached, and the flat spot is still there on takeoff.

It also is leaking oil pretty badly. Pull up at a rest area and instantly there's a dozen spots on the ground become visible. Oil use seems to be about a quart in 1500 miles, and while I first thought this must mean it's burning it, it can't be doing that badly if there's so much leaking out.

I plan to spend a bit of time checking it over when I get to Arkansas, I'm thinking I should look for an air leak on the intake somewhere that might be causing the flat spot and low power. Other things might be fuel filter, fuel pump (where are these loaced?) and if I can get someone with a multi-meter to check the power drain on the fuel pump I will try that too.

This conversion van is not too bad inside, some flaky paint on the outside, but looks very good for rust. Any advice would b e appreciated.

 

Fuel pump is in the tank. I *think* the filter is external..... Somewhere along the frame rail. Flat spot may be TPS, may also be suffering from a cat that is breaking down, or an O2 sensor that is just tired. Oil leaks, I would look at valve cover gaskets, and possibly rear main seal. I think it's a two-piece on the LA motors.....

 

The amount of oil around at the front seems to me to indicate front main seal...

I'll keep those sensors in mind when I'm looking over stuff in a wrecking yard tomorrow. While I'm not keen to do much work on this in the USA, it won't be a bad thing to have bits I can play with when I get it back home. Fuel filter and air leaks I'll look at here, and get a multi-meter on the fuel pump to see if it's the problem. If it is I might change the pump here, but the thought of experimenting with sensors in the muck around the engine is not appealing during the trip when I feel I can live with the problems for the duration.

One more thing, the overdrive off switch doesn't do anything, in fact I feel sure it's not changing up into overdrive. The tranny was said to have been rebuilt, I wonder if something's been left off or even if they've simply fitted a 727 in place of the 518.

 

On the newer trucks, the O/D off button is just a momentary switch, that sends a signal to the PCM, telling it to disable O/D...... Pressing it *should* turn the O/D Off light on.... (does that one test at startup?) If it doesn't, couple possibilities there, broken wire for the switch, or, PCM swapped to one that didn't have O/D. If the trans was swapped, but not the PCM, it should whine about No O/D, and set a code. See if you can get the numbers off the trans. Should be stamped into the pan rail on the drivers side.

Yeah, front main seal is a good possibility. If you go after that one, replace the balancer as well. It's likely grooved, and I have never had any success driving the 'repair sleeve' onto one. They always wrinkle on me, which renders them useless.

 

A further problem (or symptom?) is emerging, stalling in traffic. This combined with the terribly stuttery takeoff could be a big issue.

Like I said, the oil leak problem won't be attended to until it reaches distant shores... unless it gets much worse...

I think my nephew would be on top of the sleeve systems, he plays that game all the time.

The transmission should be a different shape to the 727, shouldn't it? A visual identification should be possible.

 

Probably... So far as I know though, the 518 is just a 727 with an O/D unit bolted in place of the tail housing....

Testing fuel pressure may not be a bad idea.... kind of a pain on TBI though..... No test port, so, have to rig the gauge inline.

 

If they did that they would need a longer drive shaft also.
Do you have a connector on the side of the trans? If so how many wires? Some of the later 727's had lock up converters but never had od. If it's 3 wire it's a od trans so not a 727. Another thing you may want to check is the # on pcm. Back then od was an option so it could have been changed to one with out od.
Yep, One look at the tail shaft housing will tell you.

 

Thank you, gentlemen...

I won't be able to effectively look into these issues for another week, I just have to keep on driving for now.

See how we go then... meantime I'm off to the wrecker's.

 

As the running has deteriorated I've decided to try a fuel filter.

I'll fit it tomorrow.

 

Fuel filter obtained but not fitted... I need to go back and get some clamps and a bit of flexible hose, so that's another day away now.

Meantime, I have to report the strangest of things. The oil leak has stopped! Oil level remains constant, driveways are no longer being stained by a multitude of drops of oil. How can that be?

And in looking underneath to see about this fuel filter I noticed:


Muffler bulging. It even looks like there's a split in the top of the crimped area there. I've had no backfires, so this is old damage.


Side-on/ You can see here the bulge in the thing, it's a wonder it wasn't blown right open, it seems.

There is a possibility, of course, that the outlet to the pipe is partially blocked, which could account for some of the poor performance.

But why is the thing shaking its head off under power now, something it didn't do before? And seemingly heavier on fuel than ever...