sealing the TD5 injector harness

[LandyAndy]

Hi Guys
Ive removed my injector harness and sealed with RTV blue Silicone.Its an easy job,I cleaned the harness with carby cleaner(I had a spare tin and it dries dry with little oily deposits) and compressed air.
There is no sealing of the wires into the components at all,not a good design.
http://www.aulro.com/albums/BlackBettys-Rack/Dsc00214.sized.jpg
http://www.aulro.com/albums/BlackBettys-Rack/Dsc00215.sized.jpg
A good coat of the RTV Blue and it should be much harder for the oil to get in.
http://www.aulro.com/albums/BlackBettys-Rack/Dsc00216.sized.jpg
http://www.aulro.com/albums/BlackBettys-Rack/Dsc00217.sized.jpg
The plastic rail isnt "oiltite" either it folds around and clips onto itself.I didnt seal that joint to allow for air expansion,it is correct way up so the oil shouldnt get in as easy,and if it does there is nowhere for it to go.
I will leave the harness off until tommorow to make sure the sillycum has set properly.
Andrew

[CraigE]

Good job Andy.
https://www.aulro.com/afvb/ https://www.aulro.com/afvb/

[LandyAndy]

Hi Craig
Is your harness bolted to the head thru that hole where the harness exits the head????? Mine isnt and there was no bolt hole that lines up.Mine just relys on the 2 Orings to hold it in place 8O 8O 8O 8O 8O 8O
Andrew

[CraigE]

Andy,
No thats it. They just pop in. They rely on the o rings and the connector underneath to keep them in position. Bloody poor design, no wonder oil ingress is likely. The o rings should be a normal service item on the LR scheduls, say every 50,000kms to avoid this. A 10 minute job that would save a lot of dramas. Like I have said it could easily have been avoided if the harness connector was inverted and had a small drain hole on each side of the connector.

[Robbo]

Well Fella's I replaced my Injector harness in the last couple of days and I think I have found the problem. I too like Andy sealed the top of each injector plug and used a tuneup insulating grease on the injector connectors. I also sealed up the top of the main plug. This plug I believe to be the cause of all the problems. I don't believe the "O"rings are the problem but I now know where the oil comes in. If you look up into the Male plug you will see an unused hole where there is no pin. This is where the oil comes through. If you hold the plug up in its normal position and spray something like wd40 around the top of the plug where the wires come in you will see the wd40 slowly start coming out of that unused hole. So I believe the problem is where the main group of wires go into there sealing rubbers at top of the plug. So in saying this I think the most important part to silicon up is around the top of this plug where the wires go through.
Anyway thats my theory.
P.S. After doing all this mine is purring like a kitten. Gone is the slight engine vibration at about 2000 RPM.

[tombraider]

Good job,

Can I offer a suggestion to you now.

Silicone doesnt like oil, so keep as good eye on your oil filters for the next change or 2.

Probably pay to rip the cover off again in 5000km's to check the condition of the silicone and that everythings going ok!.

Cheers
Mike

[tombraider]

Originally posted by CraigE
Andy,
No thats it. They just pop in. They rely on the o rings and the connector underneath to keep them in position. Bloody poor design, no wonder oil ingress is likely. The o rings should be a normal service item on the LR scheduls, say every 50,000kms to avoid this. A 10 minute job that would save a lot of dramas. Like I have said it could easily have been avoided if the harness connector was inverted and had a small drain hole on each side of the connector.

Why replace the O'rings????

High Temperature O'rings are rated over 230 c and should outlast your engine hoses.

But I agree your other suggestion (the inverted plug etc) are great ideas!

Cheers
Mike

[CraigE]

Should, but they do not, when I pulled mine out it was obvious that oil was passing the o rings, even though they looked good. I have cleaned up my old one, heatshrinked all the wiring and siliconed the ends, wil get new o rings and if I have to use it will silicone the plug into the head to seal properly.

[tombraider]

May as well not fit the orings then.

Fitting silicone to orings defeats the operational design of orings in the first place.

Make sure you order "Viton" o'rings and preferably the ones from the USA not Tiawan which most shops sell.

And yes, I know, exactly what I'm talking about.

18 years in the hydraulic sealing business.

Cheers
Mike

[stevo]

Looks like I'll be doing mine soon will heat shrink the ends and change the 'o' rings in the plug may use one's that have a slightly bigger cross section.How easy was the plug to pull out and push back in if hardly any resistance then the o rings may have insuffecent crush on them to seal properly.

[CraigE]

Tombraider,
I do not doubt your knowledge at all and it was a bit of a surprise to find that oil had actually gotten past them. I am thinking that maybe as the unit is not held down with anything other than the o rings holding it in place that there may be some movement / vibration over time wearing a small portion of the or ing away. When I pulled them out they did not look deformed or severely worn at all, but when I put them up against the new unit, they were ever so slightly worn / smaller. You could hardly notice until you laid them on top off each other. I would not silicone where the orings are. Was just thinking about sealing the top section where the plug meets the head, about 3/4 - 1 " above the o ring location. You would think with two o rings it would be just about fool proof.
Who would supplu the Viton O rings so I can get some spares.
Cheers
Craig

[tombraider]

Originally posted by CraigE
Who would supply the Viton O rings so I can get some spares.
Cheers
Craig

In WA I'd recommend a phone call to Russell Pitcher at Transeals in Welshpool, Perth.

You'll need the cross section and the O.D of the hole in the head would be best info (otherwise give dimensions off the old harness)

Tell Russ that Mike Hayes sent you and he should look after you well.

Remember you want Viton material.

He can be emailed at russellp@transeals.com.au

Cheers
Mike

[haydent]

here is my post on dissection of a loom sealed with blue rtv im guessing ~100k km ago, that was now playing up big time:
http://www.aulro.com/afvb/showthread.php?p=1818623#post1818623