Re-torquing 1.6 Hdi injector bolts

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ejuvonen
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My Cars: Citroen C4 HDi 2009
MB 201 2,5 D 2001
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Re: Re-torquing 1.6 Hdi injector bolts

Post by ejuvonen »

I have DV6TED4 and injector nuts torque is 4 Nm + 65º. I find it difficult to tune it exact because of tools ( meny connections, angle tool ) !
I was measuring 4 Nm + 65º is 7.5 Nm. 4 Nm + 65º ficure is for automatic systems, for robots.
In any case, I cannot understand why this copper seal is so childish ! Or there is unaccurate robot system ? We have every day problen with the leaking gasket in miljons of motors and there is no service instruction to get better seal. I cannot understand PSA politics in this matter.
We are byeing Europian cars to support employment.
Anyhow the Common Rail system is sad technically. Lot of big problems even in trucks ( Cummins )!
So do we have to bye Far-East cars to get Europian Industri to understand our needs for better Quality Cars !
LittleOldSuzi
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Re: Re-torquing 1.6 Hdi injector bolts

Post by LittleOldSuzi »

Sorry for resurrecting an old thread but I am trying to get the studs out of a 2009 DV6 and it strikes me that something has been overlooked (or I am being daft which is always possible).

I have 2 studs out already and there is no thread in the rocker cover, the reason the stud is so long is it screws into whatever is below, presumably the cylinder head or a ladder. I haven't had to open one up yet so I would know but it is definitely not the rocker cover that holds the studs.

My question is this, if this is a torque to yield bolt, which the extra 65º suggests, and the yield is in the M6 section below the flange where it is underneath rocker cover, why don't these studs all leak oil? Let me explain. The only thing that seals these studs to the rocker cover and keeps the oil inside is the fact that the flange is a tight fit. Ever if the yield is only a few thou that extra length would mean the flange was no longer a tight fit on the rocker cover and it would leak.

These studs don't leak so something doesn't add up. I suspect they are heat treated and they stretch above the flange but if that is the case why are they snapping below the flange. Any thoughts....
ejuvonen
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Location: Central-Finland
My Cars: Citroen C4 HDi 2009
MB 201 2,5 D 2001
Reanult Clio 1.4 autom. 2000
Fiat Ducato 2.5 TD WM 1991
Fiat 1.6 twin cam 1978
Saab 96 V4 1972

Re: Re-torquing 1.6 Hdi injector bolts

Post by ejuvonen »

These are the only GOOD injector seals !
I cannot anderstand why all the other motor manifactures are not using these ?
https://www.ebay.com/itm/254920348824?e ... SwgX5gYRkg
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2010 Peugeot 207 SW 1.6 8v HDi 161k and rising
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Re: Re-torquing 1.6 Hdi injector bolts

Post by citroenxm »

rocker cover has to come off to get the studs out. I'm not sure why you would need to get them out. they do screw into the head. if I found one loose I just use an 6mm socket to tighten it up. at each service I use a 7mm Allen key and a spanner and just check the clamp tall nuts to see if any are lose.. our 207 sw 1.6 hdi now on 183k. I've not touched a thing till 2 weeks ago when I put a set of lower milage injectors in.. with new seals to improve starting which it has considerably.
Sharing a pug 207 1.6 hdi Sw 16v.
M reg Xm 2.1 td auto exclusive S2 269k and rising
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A very sad...
1994 XM 2.1 d auto
LittleOldSuzi
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x 6

Re: Re-torquing 1.6 Hdi injector bolts

Post by LittleOldSuzi »

citroenxm wrote: 26 Apr 2021, 18:17 rocker cover has to come off to get the studs out. I'm not sure why you would need to get them out. they do screw into the head. if I found one loose I just use an 6mm socket to tighten it up. at each service I use a 7mm Allen key and a spanner and just check the clamp tall nuts to see if any are lose.. our 207 sw 1.6 hdi now on 183k. I've not touched a thing till 2 weeks ago when I put a set of lower milage injectors in.. with new seals to improve starting which it has considerably.
I am trying to get them out because they have been used to many times and the nuts keep coming loose. They are apparently single use studs (according to the PSA/Ford manuals) but people often reuse onto them because they have a habit of snapping if you try to remove them. I suspect at least one of my remain 6 studs will prove this concern correct. That said, I myself have reused the studs before on other DV6's and not had a problem and I am beginning to regret trying to do this by the book. Passed the point of no return on this one so it will be what it will be and cussing shall commence Saturday when I am home....
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2008 Peugeot 207 Sw 1.6 16v hdi. 217k and rising
2010 Peugeot 207 SW 1.6 8v HDi 161k and rising
x 70

Re: Re-torquing 1.6 Hdi injector bolts

Post by citroenxm »

there was a clamp mod done early on in dv6 life.. not sure why or if it was because of the slackening of bolts..
Sharing a pug 207 1.6 hdi Sw 16v.
M reg Xm 2.1 td auto exclusive S2 269k and rising
L reg XM V6 12v SEi auto .. Light project

A very sad...
1994 XM 2.1 d auto
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Re: Re-torquing 1.6 Hdi injector bolts

Post by cristian-Norway »

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Re: Re-torquing 1.6 Hdi injector bolts

Post by MattBLancs »

As mentioned in another thread, my attempt at solving this is to replace the standard nuts (tubular with Allen head) with M7 Nyloc nuts instead.

I have had one stud shear on removal - it was the bottom of the M7 section, leaving just the flange that tightens against the cam cover.


To answer another thought - M6 thread is 6mm outside diameter. M7x1.0 thread is 6mm minor diameter, so it is in theory possible to cut a new thread in the aluminium (of the cylinder head below the cam cover) without it being compromised by the previous M6.

I'd source M7 hardware first though, my "go to" engineering supplies place didn't have anything in M7 at all (eBay for the M7 Nylocs)

Matt
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Re: Re-torquing 1.6 Hdi injector bolts

Post by Slick8 »

MattBLancs wrote: 06 Aug 2022, 10:33 As mentioned in another thread, my attempt at solving this is to replace the standard nuts (tubular with Allen head) with M7 Nyloc nuts instead.

I have had one stud shear on removal - it was the bottom of the M7 section, leaving just the flange that tightens against the cam cover.


To answer another thought - M6 thread is 6mm outside diameter. M7x1.0 thread is 6mm minor diameter, so it is in theory possible to cut a new thread in the aluminium (of the cylinder head below the cam cover) without it being compromised by the previous M6.

I'd source M7 hardware first though, my "go to" engineering supplies place didn't have anything in M7 at all (eBay for the M7 Nylocs)

Matt
Did the M7 nylocs work?
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Re: Re-torquing 1.6 Hdi injector bolts

Post by MattBLancs »

Slick8 wrote: 13 Jun 2023, 04:43
Did the M7 nylocs work?
Seems so - been on about 3 years so far. Less mileage than it used to (lockdown, changing work conditions since then, etc) but they were still all as should be last time I checked. Will check again this week sometime (if I remember!)
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Re: Re-torquing 1.6 Hdi injector bolts

Post by Slick8 »

MattBLancs wrote: 13 Jun 2023, 07:24
Slick8 wrote: 13 Jun 2023, 04:43
Did the M7 nylocs work?
Seems so - been on about 3 years so far. Less mileage than it used to (lockdown, changing work conditions since then, etc) but they were still all as should be last time I checked. Will check again this week sometime (if I remember!)
So I'm getting loose injector caps also, a lot of fuel leakage also from injector/cam join. I fear I have other problems though like serious crankcase blowback. I think this was caused by excessive fuel/oil. So quite a few things going on. My fear is if I really bolt these injectors down, something is going to blow. The worst case scenario is hydrolock right?

It just doesn't necessarily feel like a simple case of injectors leaking due to loose caps, bad seals in my van etc maybe it is though.

I fear my valves may be damaged, or some blockage somewhere causing excessive biuld up of gasses.
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Re: Re-torquing 1.6 Hdi injector bolts

Post by MattBLancs »

To my knowledge, only risk of "really bolting them down" is risk of shearing off the mounting studs - either at the transition from top M7 to the "lump" which pins down the cam cover, or worse still further down on the M6 section in the head itself. I don't like the thought of either of those scenarios! So would not recommend increasing the torque over standard.

The Nylocs are only an attempt to prevent vibration loosening them off over time (which the standard ones seem prone to)

If you've significant quantities coming up past the injectors then I'd think new copper "fire washers" (at base of injector tip) and possibly also refacing the injector seat in the head = improving that seal is what's required I'd say. And the Nylocs to then help keep it that way.

Excessive blow by - take oil cap off and see if lots ejected there (bear in mind cam keen on flinging oil at you, mind your eyes!)

Diaphragm in the cam cover was split on mine, they are available aftermarket. This won't make excessive blow by, just controls where it goes.

Don't think hydro-lock is a risk - massive injector leakage filling a cylinder with engine off, then attempt to start= only way I could think a fuel system fault could give a hydro-lock challenge to the engine. And think an injector in that condition would give other running problems too.
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Re: Re-torquing 1.6 Hdi injector bolts

Post by myglaren »

Is there room on the thread to lock a second nut to the ones already holding the injectors in place? Perhaps a pair of thinner nuts would work.
A technique taught to me by my dad.

https://www.boltscience.com/pages/twonuts.htm
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Re: Re-torquing 1.6 Hdi injector bolts

Post by Slick8 »

MattBLancs wrote: 13 Jun 2023, 08:50 To my knowledge, only risk of "really bolting them down" is risk of shearing off the mounting studs - either at the transition from top M7 to the "lump" which pins down the cam cover, or worse still further down on the M6 section in the head itself. I don't like the thought of either of those scenarios! So would not recommend increasing the torque over standard.

The Nylocs are only an attempt to prevent vibration loosening them off over time (which the standard ones seem prone to)

If you've significant quantities coming up past the injectors then I'd think new copper "fire washers" (at base of injector tip) and possibly also refacing the injector seat in the head = improving that seal is what's required I'd say. And the Nylocs to then help keep it that way.

Excessive blow by - take oil cap off and see if lots ejected there (bear in mind cam keen on flinging oil at you, mind your eyes!)

Diaphragm in the cam cover was split on mine, they are available aftermarket. This won't make excessive blow by, just controls where it goes.

Don't think hydro-lock is a risk - massive injector leakage filling a cylinder with engine off, then attempt to start= only way I could think a fuel system fault could give a hydro-lock challenge to the engine. And think an injector in that condition would give other running problems too.
Thanks.

So my problem started when I put van in for timing belt change, the cam timing chain (16V) slipped a few teeth inside and they started and revved the engine with this slipped chain. Now garage said wasn't their fault and that no damage was done to valves, cams or rockers but they would take cam carrier off for me too see. I took carrier home and replaced chain and tensioner. Took it back to them and they said they will put it back together when they have time. Two weeks later I get impression this could last months. So I tow car back to mine and decide to put it back together myself.

I think it went ok, putting chain, tensioner and cam carrier back on went good. I took my time and followed the instructions. I put they rest back together and changed the black O injectors seals.

So van started right away but I quickly notice a lot of thick white smoke from exhaust. It turns out this is from oil leakage from turbo into the exhaust. I'm also getting white smoke from what seems like every place the smoke can find to escape, glow plugs, inlets, injectors etc. So essentially a smoke test, it's really interesting to see the leaks in your engine. I think some of the white smoke is unburned diesel also. I'm getting a lot of fuel leakage from injectors. So I run van like this I hear diesel knock(sounds a lot like rod knock) and some spluttering coughing noises. I switch van off after a minute and it doesn't shut off right away the beginnings of runaway etc for a couple of seconds. Scary.

Then I check the "oil" level it's WAY up. I drain oil to find maybe 2-2.5 litres of diesel in the oil. I think this is what caused the oil leakage failure in the turbo. It's known that if too much oil in engine then the turbo oil feed pressure becomes unsynced plus the fuel really thinned the oil.

So all in all I'm thinking it's mainly air leaks causing all this, maybe a bent valve though from when garage ran van with slipped chain. But it could just be the injectors haven't been sealed down properly.

I'm really puzzled as to how that much fuel got into the oil/engine.

Any ideas?
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Re: Re-torquing 1.6 Hdi injector bolts

Post by darbuck »

It sounds like a few injectors are stuck open pushing fuel into the oil. I would suggest a leak off test to determine which if not all injectors are kaput and change them if you can get them out of course and a diagbox session.
Darren
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