Anybody Help!?
Had a problem with a buzzing from passenger door column since having replacement engine fitted 5 mths ago. After period of time became more and more difficult to start, until yesterday where now refuses to start and just BUZZZZZZ at me.
At beginning of problem after starting would sometimes continue buzzing, but i could disconnect it and this would continue running no problem. Also after initial start could leave one side of relay unplugged all day, and starting would be no issue.
Located buzzing to GLOW PLUG RELAY located in passenger door column. Asked for advice from few mechanics, auto electricians and keep getting different stories.
Do i need to replace relay? Has something been wired wrong to cause relay to fail? Does anybody have one as i cant locate one in any breakers in the Colchester/ Essex area.
Testing last night found that i was only getting 4 volts at plugs, now after re-wiring feed wire to glow plugs am getting 7 amps, is this correct?

Would be grateful for any help with these problems.
Cheers,
Lee.

- (#13023) Lee Parker, 26 Aug 04 06:17

See http://www.mpvi.net/im/rm289e92/ewd/04gplugs.gif for help with circuit.

The Glow Plug Resistor is a thick black disc mounted on the inlet manifold with connections going to both ends, to the two glow plug relays and elswhere. Its function is to drop the "afterglow" voltage supplied to the plugs after the engine has started for a minute or two. It is easy to have the wires connected wrongly to it after they've been off.

- (#13023) Dave Mason (Sussex), 26 Aug 04 08:02

The relay in the door pillar is the secondary relay for the 'afterglow'. At the plugs when cold you should get an initial 10.5v then when the light goes off on the dash (up to temp) it drops down to about 4v.

I suspect that your mechanic has connected up the leads to the resistor on the inlet manifold wrong causing a short and the buzzing. The same happened to me. If you pick up a thread on the subject from about a month ago in the archives, all should be explained. Meanwhile, I'll take a pic of the wiring setup and send it to you. Seems to be a common occurrence this.

- (#13023) Ian Dunse (Derbs), 26 Aug 04 08:06

Bugger! Just realised the wife has the camera and she's away until Sunday. I'll try and explain how the wires should connect up. Assuming the wires at the relays haven't been touched, the two potential areas for screwing up are the glowplug resistor and the connecting point for the glowplug bridge (the flat pice of metal that connects all the glowplugs together).

Connections at the Vertical 'bolt'.

This is situated on the inlet manifold between #2 and #3 plugs. There are 3 connections which should be isolated from the bolt itself as it is earthed. They are the flat piece of metal that connects to the bridge, a wire that connects to the glowplug resistor and another wire that connects to #1 glowplug relay via a black connector.

Connections at the glowplug resistor.

This is what looks like a large bolt coming out horizontally from the side of the inlet manifold, located up and to the rear of the fuel pump. Again 3 wires. 2 larger ones to the rear of the resistor, touching each other. One goes to the aforementioned vertical connection point, the other goes off to #2 glowplug relay. Then there's a large tin covered plastic washer followed by a smaller wire and held on by a 10mm nut.

As you don't seem to be blowing the 80A fuse I suspect something isn't connected. If all still seems ok, let me know and I'll scan you the glowplug section from the manual. It details how to check each of the components.

- (#13023) Ian Dunse (Derbs), 26 Aug 04 08:49

That would be really helpful, many thanks. Would the relay or anything else been caused damage over this ammount of time that it has been connected incorrectly??
- (#13023) Lee Parker, 26 Aug 04 09:06

Doubt it. The fuse usually goes first. I'll send you the scans when I'm back at work tomorrow and have decent bandwidth.

- (#13023) Ian Dunse (Derbs), 26 Aug 04 09:15

There's also an important earth connection between the relays and the inlet manifold.

Fuses are there to take the damage, in theory.

Maybe, Ian, this is an opportunity for a sequel in Ace Answers to your well-received "Vacuum pipes" explanation?

I have to re-assemble this area on my engine in a week or so - long enough for memory to become hazy. On disassembly I observed that the first thing that could go wrong is making sure the insulators and the resistor go on the stud in the right order - so I left everything assembled as far as possible - an advantage Lee does not have. Then I thought the eyelet size difference meant you could follow the rule, "if it will go on put it on". When you say "larger ones" I think you mean larger eyelets, not thicker wire?

- (#13023) Dave Mason (Sussex), 26 Aug 04 09:38

Yes Dave I meant the size of the eyelets as you call them. In the early days of ownership when I was fumbling around trying to find out what was what (still doing that 5 years on!) I found that after a head gasket change the dummy mechanic had connected one of the wires destined for the resistor to the nearest bolt instead, which just happens to be earthed! Also the upright connector on the manifold had no insulation such that the wires that connect to the bridge were all going to earth as well.

That was just the start of my glowplug troubles. I'll see about putting a glowplug article together for Ace Answers.

- (#13023) Ian Dunse (Derbs), 27 Aug 04 01:02

Lee

My e-mail to you has been returned, unable to resolve your e-mail address. Could you check and let me know?

Ian

- (#13023) Ian Dunse (Derbs), 27 Aug 04 06:41

Ian

There is a chance my wife may have unwittingly bounced it. Is there any chance you could re-send it with TOWNACE as the subject?

Many thanks

- (#13023) Lee Parker, 27 Aug 04 11:03