Re: 2.2 DCI Injector bolt thread size?

Pm me your address and i will send you some

 

Re: 2.2 DCI Injector bolt thread size?

Pm me your address and i will send you some

I got them. Thanks for that. It was a very generous offer. I owe you one. :beer:


The injector came out pretty easy by slackening the bolts bit by bit with the motor running. I wish I could report a success after that..... When I got down to the job I discovered somebody had been at this injector before me and botched the job. They had stripped one of the cylinder hole threads that the bolt goes into. They had fitted a Philips pan head bolt that was a bit longer to go past the stripped section. (The thread is 6mm by the way. 50mm bolt)

I'm now going to have to put a 7mm tap down it and get a 7mm bolt to fit. I'm going to do both as I think the other bolt hole thread is ready to go as well.

Tracking down 7mm Torx bolts proved to be a non starter. I finally found some Allen bolts in 7mm on the net that should do the job.

I'll let you know how that goes in due course.....

All the best. :d

 

Re: 2.2 DCI Injector bolt thread size?

You are a star! :d Thank you. PM sent.

 

Re: 2.2 DCI Injector bolt thread size?

You could put a helicoil insert in,therefore allowing you to use the proper bolts.

 

Re: 2.2 DCI Injector bolt thread size?

:d Not really an option when the job has about 5" of space under the scuttle of an Espace 4 and you are working with a mirror to see what you are doing. Can't use regular bolts anyway. The injector are in a deep recess. It needs a 100mm long thin tool like a torx or an allen key to tighten the bolts.

 

Re: 2.2 DCI Injector bolt thread size?

OK Job done..... but still not right.

Not a lot of room to get the tools in deep down in that rocker cover - but not to difficult with the correct tools. Tapped the stripped injector bolt hole out to 7mm. The other bolt was fine so left that. Cleaned out the recess for the injector. Carefully cleaned the seating face and the injector. Fitted new fire washer, tightened it all down........... AND it still leaks! Just a faint trace of smoke when hot.

I've tried tightening down each bolt incremetally while the engine is running for only a minor improvement.

Took it all apart again. Cleaned it all up - no signs of the injector seating (or the injector seat itself) being damaged or scratched. Fitted new fire washer. Motor runs fine but the seal is still leaking on tickover. Disappears when revved above anything over tickover.

Any suggestions on how to cure this tiny leak?

 

Re: 2.2 DCI Injector bolt thread size?

Just in the process of doing all my injectors following a damaged cambelt forcing me to take them out to get the rocker cover off! I'm going to anneal the copper seals before I put them in and give them a coat of copper ease. I'm hoping that'll give me a gastight seal....
Do your injectors also have the anti vibration kit - plastic sleeve and 'O' ring? I would have thought that if you had just a small leak at idle, that might be enough to hold it back? I'm also going to use ceramic grease on those parts.

 

Re: 2.2 DCI Injector bolt thread size?

Just in the process of doing all my injectors following a damaged cambelt forcing me to take them out to get the rocker cover off! I'm going to anneal the copper seals before I put them in and give them a coat of copper ease. I'm hoping that'll give me a gastight seal....
Do your injectors also have the anti vibration kit - plastic sleeve and 'O' ring? I would have thought that if you had just a small leak at idle, that might be enough to hold it back? I'm also going to use ceramic grease on those parts.

I would be doubtful that the copper ease will do any good. It is only usefull up to 1150 c. Above that temperature and it is no use. There is no mention of using any sealents in the manual for this engine on the injectors. The O ring and sleeve are just to keep the injector sitting square in the head. The copper fire washer is the gas seal. Once it gets past that the O ring won't hold the extremely hot gasses in. I would use new washers if I was you, they cost only a few £'s

I think madnoel offers the only solution unfortunately.

 

Re: 2.2 DCI Injector bolt thread size?

Annealing the washers odesn't mean they will go back to their original condition, shape or size.
Also no sealing compound or grease should be used on the sealing faces of either the head or injector as it is likely to carbonise and/or create hot spots leading to further failure.

If after cleaning and refitting the injector it still leaks then something is amiss with the jointing faces. Whilst they may look perfectly clean they may not be true. Most diesel fitters use a special reamer to clean the seats before assembly. It is known for escaping gases to actually bend the injectors due to high temperatures.
If an injector continues to blow there is a high risk of damaging both the injector and the cylinder head and as neither is a cheap repair it's best to sort it correctly.
The temperature and pressures in and around injectors are extreme to say the least so it only takes the smallest amount of error to lead to problems.

 

Re: 2.2 DCI Injector bolt thread size?

Well well... Fired the engine up today and took it for a good long drive to warm it up prior to removing the injector and the injector looks like it has seated itself. No leak.... I can only assume that the pressure of the bolts over 24 hours has finally squashed the copper washer down and it has sealed itself properly. Just took it for a good fast drive and it seems to be fine. I'll be keeping an eye on it though till I'm certain.

 

Re: 2.2 DCI Injector bolt thread size?

Good news, rodmaker, hope it stays good.
I bought new seals today after the advice from madnoel! Hope the new injectors come tomorrow. Also bought the new injector studs which replace the old torx screws....

 

Re: 2.2 DCI Injector bolt thread size?

Good news, rodmaker, hope it stays good.
I bought new seals today after the advice from madnoel! Hope the new injectors come tomorrow. Also bought the new injector studs which replace the old torx screws....

That wil lexplain why I cant get hold of the screws any more. I had a look at a parts diagram at Renault and is showed studs with a spacer and then a nut on top. Im guessing this has replaced the screws as I am having the same problem as you?

 

having issues too are there any other bolts i can use ?,i think £54 plus vat is joke only need 2 bolts also i need to rethread the holes what size are they? just want to make sure its right

 

Thread ressurection!

Just my 2p worth, and findings.

Standard Torx bolts are TTY (Torque To Yield) and should only really be used twice. My 2.2 DCi espace needed an engine rebuild. Big end bearings totally shot (pistons hitting head!!), also no 4 injector blowing like a steam train. While I was there with the head off I checked the injector seats and saw that 4 was knackered so re-cut them all. I also helicoiled the bolt holes and replaced the standard injector bolts with M6 x 50 12.9 cap (allen) head bolts. A calculation showed that to replicate the TTy bolt's clamping torque it would require 16Nm of torque on the flywheel side bolt (only one is high torque). Pretty high for the threads in the head?!

Anyway, after a lot of torquing and chuffing and relaxing bolts and re-torquing.... I got to the stage where the injectors would blow on a weekly basis but I was dreading pulling the threads out of the head when getting up to the high torques! Finally I found that pulling the bolts up to 15Nm hot initially, and then re-torquing once cold has worked for good and the chuffing has ended.
It may feel like the threads will give way, but to replicate the TTY clamping loads you need to be brave and get to 15Nm. But an accurate, small torque wrench is essential.

 

Hmmmm
Torque to yield on an M6 12.9 would be in excess of 20nm.
95% of yield stress on M6 cap head is 19.1nm
TTY bolts should only ever be used once. They are being stretched right to the yield point and if stretched again may well exceed
Apart from that, yup, 15nm is a reasonable torque for that size bolt but not into the realms of Torque to Yield.

If you get a standard allen key (5mm ??) and give it a good grunt, that is about 15nm.
Where people make errors, is using a 1/2 ratchet with a hex bit on the end and give that a good grunt. Well over the recommended torque and the threads in far weaker aluminium suffer.

New copper washers and clean seating faces are the other key to chuff chuff free motoring.

 

The clamping force of a std Renault bolt is equivalent to 16Nm on a 12.9 bolt with oiled (or Loctited?? May help it to not loosen) threads.

Yes a cap head (allen key) bolt is 5mm, but a good grunt is hard to measure. I found that its very difficult to 'feel' the torque as the threads really do feel like they are giving way as you go above 14Nm. Luckily 15Nm does the job.

Agreed that if you are going to use to use bolts other than std then just using a ratchet with a hex but and pulling until its FT will only lead to more problems.

My learning point, a very accurate 1/4 drive torque wrench (0-20Nm) and testing in increments up to the calclated value of 16Nm...... Also knowing when to stop!

I wouldnt want to yield a 12.9..... Not on my engine anyway lol

 

Fully accept that it is difficult to calibrate a good grunt :grin2:
Which is why torque wrenches were invented.

And is also the reason why spanners and Allen keys are differing lengths, supposedly so the "average" guy gets it something like right by using the "give it a good grunt"

Of course, what the 8 stone weakling who struggles to open a new jam jar considers a grunt is going to be far different to what the strapping hulk who spends half his time pushing weights thinks it is.
And people stick a length of pipe on the key or spanner and then give it another grunt for good measure.

Point is that 15nm is a lot lower then people think is needed or can easily achieve with too much leverage.

In that respect, a decent torque wrench is a very good idea.

People do the same with other fittings that go into cylinder heads...... Glow and spark plugs are two prime suspects that are often overtightened.

Must admit that true stretch (tension to yield) bolts such as cylinder head bolts, scare the pee outa me.
I know that if I follow the preset torque and angular tighten that is all I can do but they always make me feel woah, too much.

 

6 foot scaffolding pole works for me,0