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Engine Specific Info and Questions => IDI Engine => Topic started by: Jay on November 14, 2009, 07:13:46 am

Title: can I run with a glow plug seated incorrectly?
Post by: Jay on November 14, 2009, 07:13:46 am
Reason I ask is that #1 GP (closest to the cam belt end) won't screw in properly and seems to be at a slight angle so I'm thinking the threads are gone on the inside of the GP hole. I've tried 2 different GP's and they do the same, they screw in fine in the the other holes.

I've done it up quite tight, but it feels like it can go a bit more, but I don't want to risk ruining the engine for good. Remember I don't have the knowledge, money, tools or know how to remove the head and have a good look at the mo.

So can I run with 3 GP's in fine and 1 not screwed all the way I, but quite tight? (hope it all makes sense)
Title: Re: can I run with a glow plug seated incorrectly?
Post by: burnt_servo on November 14, 2009, 08:56:54 am
a previous owner to my car cross threaded the same glow plug ( the one directly behind the injection pump , closest to the timing belt .... ie cylinder #1 ) .

had a hell of a time removing the glow plug , and when i put the new one back i i worked it back and forth in the threads till it felt like it seated into the head .
that lasted 2 1/2 years till i changed the head out last july . ( the head had cracked through the cumbustion chamber  due to a blown rad hose  , and the driver not paying attention / having the radio cranked up really loud  . )

you do risk having the glow plug working the threads loose and  blowing  out , and having the car run on just 3 cylinders .

to repair it you need to remove the head , or find a new head , so if you don't mind the possibility of having to get it towed home when you least expect it ,make sure the glowplug is tight , and   drive it .

i'd also start looking for a head , and putting some money aside to repair it when the time comes ...... because it will.
Title: Re: can I run with a glow plug seated incorrectly?
Post by: burn_your_money on November 14, 2009, 09:34:25 am
I have a link at home to a thread repair/reamer for the glowplug holes. It may work for you. I would not advise trying to tighten the glow plug up any further.

Odds are it isn't going to seal like that. You could try using some permatex thread sealant and seeing if that helps any. Really though you should do it right or you risk seriously damaging the head. You may even need a helicoil.
Title: Re: can I run with a glow plug seated incorrectly?
Post by: burnt_servo on November 14, 2009, 11:00:07 am
in my previous post , i'm assuming his head is already damaged , and in need of repair  .

do you have that link handy for that reamer ?
Title: Re: can I run with a glow plug seated incorrectly?
Post by: the caveman on November 14, 2009, 11:37:07 am
Well you can look straight at while revving the motor to see if it'll blow out. Oh wait DON'T DO THAT !! ;D
Title: Re: can I run with a glow plug seated incorrectly?
Post by: Jay on November 15, 2009, 12:46:01 pm
Well we tried firing the car up today (see other post about driving into deep water) and smoke was coming out of the GP hole, I hadn't done it up tight at all today.

I think this is a defo a job for Crazy Quiff's (MK1 specialists less than 500yards from my front door  ;D )
So I'll call them tomorrow and see of they can rethread it with the head on, possibly using a Helicoil too.
Title: Re: can I run with a glow plug seated incorrectly?
Post by: burn_your_money on November 15, 2009, 03:28:54 pm
If you put the engine near TDC and force an intake valve open you should be able to hook a vacuum up to the injector port to pull any fillings out of the engine if they have to drill/tap.

I'll try and remember that link tonight when I get home...
Title: Re: can I run with a glow plug seated incorrectly?
Post by: gldgti on November 15, 2009, 11:54:55 pm
i reckon a helicoil would be the sensible option - maybeleave the head on by remove the pump.

then again, both operations probably take similar time...
Title: Re: can I run with a glow plug seated incorrectly?
Post by: Jay on November 16, 2009, 12:42:47 pm
£400-£500 for them to fit a helicoil  :o
That's for a 'proper' job of removing the head, drilling and fitting a helicoil, installing a new timing belt tensioner & head gasket and checking the head to see if it needs to be skimmed etc.


That's wayyyy to much for a car that's a Category-C write off and I'll never get money back on.

So I'm going to try and bodge it with high temp thread lock type stuff and force the bugger in.

It'll do until it dies or MOT runs out next June when it gets garaged for a future project.


Any suggestions on good high temp Thread lock type stuff that I could use?
Title: Re: can I run with a glow plug seated incorrectly?
Post by: burnt_servo on November 16, 2009, 04:37:50 pm
i used blue locktite .

when i forced the glow plug into my engine , worked it back and forth with a old glow plug till the taper on the glow plug appeared to be seating . make sure you grease the threads when doing this .

this is also a one time thing , a temporary patch of sorts  till you can save enough money to fix it yourself properly .

also if you do this , put some money aside to have the car towed home  , and keep it in the glove box  ..... just in case .
Title: Re: can I run with a glow plug seated incorrectly?
Post by: Jay on November 17, 2009, 08:06:36 am
i used blue locktite .

when i forced the glow plug into my engine , worked it back and forth with a old glow plug till the taper on the glow plug appeared to be seating . make sure you grease the threads when doing this .

this is also a one time thing , a temporary patch of sorts  till you can save enough money to fix it yourself properly .

also if you do this , put some money aside to have the car towed home  , and keep it in the glove box  ..... just in case .

Cheers for the info  ;D  I've got a tube or two of that blue locktite around somewhere.

I make sure I have recovery included with my insurance, I've had to use it a few times on the old girl already  :'(
It's only a temporary 'fix' (read bodge) until I get my new car.
Title: Re: can I run with a glow plug seated incorrectly?
Post by: burn_your_money on November 17, 2009, 07:35:01 pm
The reamer is somewhere on this page, I can't find it right now