Gq TD4.2L Hard to start/wont rev out

[Bunsen8]

Hi Guys, Great forum. Ive fixed sereral issues on my GQ which would have cost me an arm and or leg if I got a repairer here in Karratha to look at. Both problems were quite simple to fix as well. I'm a fitter by trade so I'm prepared to try fix anything myself.
I use my 1989 GQ Patrol TD4.2L mainly as a boat puller. Its got plenty of grunt,but lately its had issues. To start with, its been a pig to start. Usually I preheat until the light goes out and she starts straight away. Not now. I have to pump the accelerator until it fires up. I can hear the glow relay activating on and off. It does this 3 times with a 3 sec break in between going on and off? This surely isnt how the relay works? Ive tested with a test light and multimeter. Battery is fine. Im getting power to glow plugs as it does this. Also, once running. It will not rev out to its full potential, like its not getting enough fuel.Are these issues related? I have changed the fuel filter. Checked theilter in the fuel pump behind the banjo bolt. All seems well. Question is, where to start now as its seems like a fuel and or electrical issue.

[Yendor]

Sorry I can't help much with the fuel side.

With the glow plug operation that sounds normal.

This is how the system works and this depends on engine temperature.

When you turn the ignition on the glow plugs will come on and stay on for a certain amount of time.

Then when you start the engine the glow plugs are then pulsed on and off for a certain amount of time.

You will need to test each glow plug to make sure it is working.

[Parra]

hi bunsen,

on the top of the fuel filter, there is a little black 'pump' primer. push that a few times then have a crack at starting it. had a similar problem a while back, and this fixed it.

good luck!

[Bunsen8]

Thanks guys. I will test each glow plug this arvo

[Bigrig]

G'day mate and welcome aboard - great people, information and laughs to be found on here, so join in to make the most of it!!!

Enjoy!!

[nissannewby]

With the age of the vehicle also (not knowing its maint history) your fuel pump could be getting a little tired also.

[Bunsen8]

Have checked glow plugs and they are fine. Now I have another issue. I disconnected battery and now Im having trouble with the alarm system. Its switched it off with the key at the siren. But it still wont allow me to start the vehicle. I can hear the starter relay try to work but this alarm wont allow any other action. Does anyone know a thing or two about Black widow BW-680 alarms? There an old system. I just want to bypass the alarm and I'll remove it at a later date once these other issues are resolved.

[97_gq_lwb]

Their is a gauze filter in the pump it could be that blocked as well quite common apparently.

with the alarm try shutting all the doors and bonnet and turn the alarm on and off a few times with the remote.

[Yendor]

Sorry I have not had experience with Black Widow alarms but I have had experience with other brands.

Most alarm control modules are mounted under the RHS dash, just above the petals.

The wiring is normally tapped into the ignition switch wiring.

If the vehicle is not cranking then I would say they have isolated the start signal from the ignition switch.

Remove the covers from around the steering column and have a look at the harness that runs to the ignition switch. You a looking for, newer looking tape or where a second harness joins into the main harness, the second harness will more then likely run to a black plastic box.

If you can see this remove the tape. You are looking for a Black wire with a Yellow trace that has been cut in half and will have wires added to each end, these wires will run to the black plastic box.

You need to cut off the added wires and rejoin the Black wire with a Yellow trace back together again. This should reconnect the start circuit.

Also, most alarms have two isolation systems, so if you can see any other of the original wires that have been cut in half and have new wires running to the black plastic box you will also need to rejoin these.

Lets us know how you go.

Cheers Rodney

[Bunsen8]

Thanks for your help guys. I ve removed the alarm completely and I'm charging the battery over night. Will test tomorrow. Cheers

[Bunsen8]

I tried to start my patrol this morning after charging the battery all night and it still wont fire up after the first glow like it use to. Took a couple of goes and lots of pumping the accelerator. I checked the fuel pump for that small filter and there isnt even one in there. Should I get another to replace it or is it ok to run without it? I also pulled out a glow plug and it seemed to have a burnt patch on one side of it. Is that normal or should it be a more even burn mark all around it? If that plug is u/s, is there a particular brand of plug which is better than others or are they all the same? Other than the burn mark on the plug,it seems ok. I tested it for continuity, all good. 0.7 to 0.8 ohms. Should I just replace the plugs so I can cancel out that issue?

[97_gq_lwb]

Did you try turning your ignition on and off a few times before starting that sometimes helps with older glow plugs that aren't working 100%

[Bunsen8]

Yep, tried that. I'm just gonna change the plugs.

[97_gq_lwb]

If you pump the primer on the top of the filter before you try and start it does it pump or is it firm.

[Bunsen8]

I can pump it 6 times and then it goes soft again haha Yes I'm still talking about the fuel filter primer

[97_gq_lwb]

viagra should fix it then .

Mine stays firm and starts first go check for any leaks might be a drainback issue caused by a leak or it may need bleeding .
It is sometimes hard to find due to the injector pump sucking the fuel up.
Some people will fit a lift pump near the tank this will force fuel out of any leaks usually.
I just used a low pressure electric fuel pump up the front on mine and it lined up with the bolts on the battery tray.

[Bunsen8]

Yep, theres a fuel leak around the fuel filter somewhere. I pumped it up a few times and it wont hold the pressure. I can hear a leak coming from that area. Theres a few drops of deisel coming out the discharge hose at the bottom of filter. I pulled it all apart thinking an oring might be damaged. Put it back together and still has this issue. Whats going on here?

[97_gq_lwb]

No idea seals shot maybe try a new filter.
But atleast you know now what your problem is.

[jedskipow]

Is is blowing smoke at rpm' . Try reving it till it misses and pumping the primer. If you have changed the fuel filter that white water drain often starts leaking( see if its wet) against fuel filter.
Stopped for gu 100ks from anywhere and servicer had done water drain back onto filter that tight it stripped the threads. Silastic, electric tape and good to go. ;)
Actually could be electic with alarm probs, run a wire to electric shut off on fuel pump you.d think it would just stop or no start if wire lose.

[Richo460]

Hi mate, i had a problem with my TD42 at 300 000, it wasn't revving out so i took it in and got a mechanic to check the injector pump, he pulled it apart and replaced all the seals and bench tested it, he said it was a bit worn out but still going ok. It seemed that the pump wasn't sucking the fuel from the tank well enough but the pressure side was fine. After replacing everything in the fuel system we put a cheap electric pump inline just after the tank to help get the fuel through to the injector pump and it worked perfectly. Haven't had a problem with it for 2 years.
This should also fix your hard to start issue as it sounds like the pump is loosing prime. This was my problem anyway.

[Bunsen8]

Thanks for all the help guys. Found a tiny pin hole in a fuel line at the filter. It wasn't leaking, but when I put my foot down on the accelerator it was sucking in some air. Simple fix in the end. Damn cars. She runs sweet now