rougher idle on uphill slope

[sandcruiser]

on my hd-t motor, when I park facing uphill, the idle drops way off... down to about 300 rpm (and sometimes dies).

it is also harder to start when facing uphill.

Any thoughts?

I'm guessing that maybe a worn motor mount (or two) could be allowing the motor to settle back and somehow affect the throttle cable, or maybe something on the IP is pulled back by gravity, but I'm interested in hearing other opinions

 

[Tapage]

I will start check the pressure on the IP ( before it ) and see hoy much fuel are you getting .. just to discard the capacity of the IP to suck diesel from the tank ..

 

[gbcruiser]

I had the almost opposite once: down steep hills, the engine would stall out and be a little hard to start. Never found out what it was though...

 

[sandcruiser]

I'm planning to add a Vacuum gauge before the IP so that when I run SVO I can tell if the filter is plugged. That should show me if the IP isn't pulling hard enough

Anyone know just how hard the IP should be sucking?

 

[Tapage]

I'm planning to add a Vacuum gauge before the IP so that when I run SVO I can tell if the filter is plugged. That should show me if the IP isn't pulling hard enough

Anyone know just how hard the IP should be sucking?

I thought ( and are only based in deductions ) more than 15 PSI and up to 60 PSI before IP, coz the diesel common electric pumps are around those ranges. .. after you are refering to the injectors pressure that could be more than 2500 PSI

Actually I run a electric that push 40 PSI in my Tencha just to help with the double filter setup ( Delphi ).

 

[sandcruiser]

I thought that the toyota IP didn't have an extra pump ahead of it, am I wrong?

 

[Tapage]

I thought that the toyota IP didn't have an extra pump ahead of it, am I wrong?

You were right .. factory diesel (unless are common rail ) don't come with electric pumps .. I do it for 2 reazons, safe my primer ( never need to push this stupid old thing again ) and coz I have one extra filter .. in my fuel line.

 

[sandcruiser]

how did you plumb in extra pump?
where is it?

 

[Tapage]

how did you plumb in extra pump?
where is it?

It's in the fuel line .. both are between the Delpli filter/water separator and the factory filter ( engine room )

 

[sandcruiser]

So i figured out and fixed the problem:

Somehow the limiting screw for minimum idle was adjusted just a shade too low--- it would idle at around 400 rpm when on a level surface.

When pointing uphill, it would idle just a little lower and get very rough. I don't know exactly why the rpms would drop pointing uphill, unless the actual weight of the IP was enough to make the armature shift just a little (a little movement=a lot of drop in rpm).

I adjusted the limiting screw, it now holds 600rpm as the minimum. No roughness on the uphill.
It doesn't idle over 600 unless the AC kicks in and raises it a little. Still needs some more adjustment, but is much better.

 

[Tapage]

I adjust my 1HD-T rpm at 800 rpm with and without AC .. ( playing with the AC compensator ) it feels much more steady IMOP ..

 

[sandcruiser]

well, I thought I had it fixed.... but today it was idling at below 600 again.
I need to check the bolt from yesterday to make sure it didn't slip, and seize it with the little wire...

also need to play with the a/c compensator a little more (and check the manual)

I still suspect that I've got some sort of fuel delivery problem as the low idle only happens when I'm parked on a steep uphill slope.

It could be as simple as a fuel line that is partially clogged

 

[70sguy]

Your sig line indicates a conversion. Were the fuel lines swapped out to the larger diesel set? Fuel pick up swapped to diesel type or at least EFI fuel pump removed?
Walbro pusher pump might solve the problem if it's a fuel line resriction problem.
To isolate the problem to either Inj pump or tank/lines, you might want to park it in a position where it low idles and then pull the feed and return lines and feed it fuel from a mason jar or something to see if it corrects.

 

[sandcruiser]

I think you might be on to something there, 70sguy. I don't think that the fuel lines were swapped and have often wondered if they made any changes to the tank...

I'll get under there to take a look.

Anyone got a picture of the "correct" fuel line routing for an hd-t?

 

[rchalmers3]

sandcruiser,

If you suspect a delivery problem, you may want to try installing a length of clear tubing ahead of the IP to visually confirm there's no air bubbles passing into the IP at idle.
If the fuel line is too small, I think you would have delivery problems at times of high demand, like driving highway speeds. Idle supply problems are more likely to be small suction leaks, c'nest pas?

Rick

 

[70sguy]

Anyone got a picture of the "correct" fuel line routing for an hd-t?

Here is what they look like on Toyota EPC.
I would bet that your lines are in the factory location, they are probably the original 3FE lines.
Pull the rear seats and carpet to access the fuel pick up to see what's going on, modified gasser pick up or
diesel pick up.

But of course run the motor out of a mason Jar first so you know which way to look.

If there is air getting into the system the first place to look is the primer pump/fuel filter cap assy, that is assuming one was installed as part of the swap.

 

[sandcruiser]

hmmmm
going to have to get under there this weekend and see where the lines go/what pickup it has.

I think that the bubbles might hold the answer, maybe something is flexing/kinking when it points uphill, and that lets bubbles into the system.

of course, first of all I've got to park somewhere level and adjust the fuel delivery w/ and w/o AC idle up.
Then I'll start checking for leaks and kinks and such

 

[onefsatchevy]

Got kids?? I know of a few instances (not with cruisers) where marbles and such have been found in the tank.... Caused all sorts of weird problems.... Just a thought...

 

[sandcruiser]

We don't have children, but the truck has only been mine for a few months... anyone's guess what happened last year!

 

[rchalmers3]

sandcruiser,

Any updates? Or has this swell been your main focus? Surf has been good down this way. Not much work getting done around here!

Rick