Auxiliary fan - purpose.

[Pinger]

More rolling blog......
At last - steering wheel is straight! Made the adjustment at the (rag?) joint at the bottom of the column just before the steering box. Fiddly - but done.

Fuel pressure as before. Key on, open Schrader, spurt. Key on, leave for a while, open Schrader, lesser spurt - as if pressure is bleeding off. I need to give this more thought. So far though, the pump seems to be kicking in as it should.

 

[east302]

More rolling blog......
At last - steering wheel is straight! Made the adjustment at the (rag?) joint at the bottom of the column just before the steering box. Fiddly - but done.

Fuel pressure as before. Key on, open Schrader, spurt. Key on, leave for a while, open Schrader, lesser spurt - as if pressure is bleeding off. I need to give this more thought. So far though, the pump seems to be kicking in as it should.

You’d really need a gauge on it to see what it’s doing. Not sure what the availability is across the pond, but you could rig something up if needed. If it met the pressure spec (60-66 psi on a 350) but then dropped off, you’d alternately isolate the supply and return lines near the fuel filter to determine the source of the leak (pump, injector(s) or regulator).

For example, say you put the gauge on and start the pump. Pressure gets to spec but quickly drops off when the pump is turned off.

You’d remove the fuel filter and install a ball valve. Charge the system, close the valve and check pressure. If it holds, then the pump is the issue - there’s a check valve that is supposed to keep the line charged.

If it drops, then it’s an injector or regulator leak. You’d put a valve on the return line (there’s a union near the filter on the 350), charge it again and close the return valve. If pressure holds, then the regulator is leaking back to the tank. If it drops then it’s an injector leaking. That all assumes that you don’t have a fitting or line leak.

GM dealers use a kit made by Kent Moore for this purpose, but they’re stupidly expensive.

 

[Pinger]

Don't have kit (just now at least) to measure pressure but repeated yesterdays 'test' today and after sitting primed for 6 hours there was still pressure.
PITA is it usually misbehaves when warm and parked among other cars. My 'spurt' test with the fuel pissing out above the distributor - could set any amount of cars alight.

More thought required but I'm more inclined by the day to suspect PassLock.

 

[HotWheelsBurban]

Don't have kit (just now at least) to measure pressure but repeated yesterdays 'test' today and after sitting primed for 6 hours there was still pressure.
PITA is it usually misbehaves when warm and parked among other cars. My 'spurt' test with the fuel pissing out above the distributor - could set any amount of cars alight.

More thought required but I'm more inclined by the day to suspect PassLock.

Yes that's the most frustrating thing about that system, is it mimics so many other things.
Without going through all your posts, have you checked all the starter/solenoid connections, and the battery cables and connections? Did the starter get any oil in it from the crankcase exploding? I had these issues with my truck earlier this year when it didn't want to start when hot. And I totally agree with you on not wanting to burn up your truck and anyone else's vehicle. With the LPG that's an even bigger risk. Don't want to see you on the news!

 

[Pinger]

Starter and all that is fine. It would crank until the battery flattened if I didn't call a halt and force start on LPG. Thereafter it will run perfectly on gasoline if I switch over to it. Which kind of says everything works but something is telling it not to - PassLock?
If/when it happens again I'll pay more attention to the 'security' light on the dash and if it can be provoked into doing the same at home - probe the fuel pressure. Without razing a carpark to the ground.

 

[HotWheelsBurban]

Yes that would be good! You just have to keep at it, process of elimination. If it's not A then look at B and so forth. Good luck, you'll find out what it is. It just takes some time and all your patience! See what I mean about our trucks being metal kids LOL

 

[HotWheelsBurban]

Yes mine would crank all day when Passlock acted up. Just wouldn't start and run very long. Since it does run fine on petrol, and seems to have no issues with rpm change on throttle up, that pretty much eliminates the fuel pump and relay. Also the throttle position sensor and idle air control valve. If either of those is bad you'll have uneven idle and throttle response. Did you change the crankshaft position sensor when you replaced the timing cover? Cause it won't want to fire if that's bad. Distributor cap and rotor good? I know you've probably looked at or replaced some of these but look again. Not trying to be pedantic, just doing what I did on my truck;process of elimination.

 

[Pinger]

Yes mine would crank all day when Passlock acted up. Just wouldn't start and run very long. Since it does run fine on petrol, and seems to have no issues with rpm change on throttle up, that pretty much eliminates the fuel pump and relay. Also the throttle position sensor and idle air control valve. If either of those is bad you'll have uneven idle and throttle response. Did you change the crankshaft position sensor when you replaced the timing cover? Cause it won't want to fire if that's bad. Distributor cap and rotor good? I know you've probably looked at or replaced some of these but look again. Not trying to be pedantic, just doing what I did on my truck;process of elimination.

Picking up on your points one by one HWB.
CPS - OK as it even when hot (when they are susceptible) it has sat for say 30 mins and merely warm. That it will fire up on LPG (a more difficult fuel to ignite) confirms that it is OK and gives a clean (enough) bill of health for the distributor and ignition system generally.

IAC I removed and checked and nothing amiss. Also, shunting on the drive here with PAS kicking in and out, the idle is stable. TPS is OK - I can read its signal on a lap top with the LPG software.

Tomorrow, I'll be firing it up after 6 days sat with battery connected re (supposed) battery drain problem. If it is misbehaving then I can probe more at fuel supply - albeit crudely at the Schrader valve. Thinking I might prime the system then remove the pump relay and see if it fires up briefly on what fuel is present. If it mimics what happens when it plays up (fires momentarily then quits) then that would point to relay being deprived signal and would correlate with PassLock bad behaviour?

Totally agree re process of elimination (and not pedantic - helpful!).

'Metal kids'! I do have kids after all then - well, one (big one)!

 

[HotWheelsBurban]

Picking up on your points one by one HWB.
CPS - OK as it even when hot (when they are susceptible) it has sat for say 30 mins and merely warm. That it will fire up on LPG (a more difficult fuel to ignite) confirms that it is OK and gives a clean (enough) bill of health for the distributor and ignition system generally.

IAC I removed and checked and nothing amiss. Also, shunting on the drive here with PAS kicking in and out, the idle is stable. TPS is OK - I can read its signal on a lap top with the LPG software.

Tomorrow, I'll be firing it up after 6 days sat with battery connected re (supposed) battery drain problem. If it is misbehaving then I can probe more at fuel supply - albeit crudely at the Schrader valve. Thinking I might prime the system then remove the pump relay and see if it fires up briefly on what fuel is present. If it mimics what happens when it plays up (fires momentarily then quits) then that would point to relay being deprived signal and would correlate with PassLock bad behaviour?

Totally agree re process of elimination (and not pedantic - helpful!).

'Metal kids'! I do have kids after all then - well, one (big one)!

That's good that you have the laptop and software to monitor how the truck runs. I wish I had that. Eventually I will get something to do that, with my tablet and an interface cable. I'm still trying to get used to the idea that a computer is as much of a mechanic's tool as sockets and wrenches. I grew up on 60s and 70s GM cars and trucks; carburetors, early electronic ignition, room underhood, etc... I know enough about the next several generations of trucks to know that l don't really want one unless it has an extended warranty. Too much expensive stuff to replace otherwise.

 

[Pinger]

That's good that you have the laptop and software to monitor how the truck runs. I wish I had that. Eventually I will get something to do that, with my tablet and an interface cable. I'm still trying to get used to the idea that a computer is as much of a mechanic's tool as sockets and wrenches. I grew up on 60s and 70s GM cars and trucks; carburetors, early electronic ignition, room underhood, etc... I know enough about the next several generations of trucks to know that l don't really want one unless it has an extended warranty. Too much expensive stuff to replace otherwise.

Lap top only works for LPG system unfortunately - and only takes in the TPS as the system reads from it (but only for fuel switchovers). I have Delphi software but it doesn't do anything for the Burb. I also have Wurth WOW! software but not much of a clue how to use it. I'm going to search the 'net for a YouTube tutorial on it when I get the time but the weather has been so good lately I'm as well outside doing other work on the critter for now.

Totally agree modern cars without a warranty are a nightmare. One of the reasons I went for the Burb. A little bit disappointed that it has so many little computers (eg HVAC) but at least that stuff doesn't strand it at the roadside.

I've been reading some of the threads about inlet manifold gasket and am starting to see that the distributor is tricky - but can't figure out why. Surely all it does is, well, distribute. Allocate the spark to the correct cylinder with the timing coming from the ECU using the CPS (and camPS for starting?). I get that with V8s the rotor arm has to be just so to avoid cross-firing but still not getting why re-installing it is so critical. Obviously, there is something I am missing.

One thing about this forum I struggle with is that I spot something on a thread and mean to come back to it and can never find it again! Eg, there is a current thread with a photo of the group of fuel injectors (spider?) as they sit on the manifold - any idea which thread that was? (Don't go searching but if you remember off the top of your head...)