Tourque settings

[Allchin]

I am just fitting new(refurbished) injectors to a 24v engine. When it comes to fitting the fuel leakage pipe, the workshop manual says the torque is 18Nm and in the Ausi WM the torque is 12.4Nm the later seems appropiate for a small bolt. Does anyone know the correct torque and also torqued the bolt themselves to that setting?

Stephen

 

[IRLGW]

what spec is the bolt. never mind the the manual...

 

[Allchin]

what spec is the bolt. never mind the the manual...

No marks on the bolt, it a purpose made for the job.

Stephen

 

[StarCruiser]

I don't know about the bolt torque which I'm guessing is the banjo bolt. Whatever you do I hope you're fitting new washers either side of the banjo as this can leak if old ones are reused. Personally I would then go with the manual for the country the truck was intended.

 

[IRLGW]

what diameter is the bolt and what is the thread pitch? You could make an educated guess based on assuming they are steel bolts and a known diameter. If you know the average torque for that size bolt and dont exceed it then you can use that as a starting point. It you are finding leaks or air drawn in then increase torque accordingly but don't exceed the torque by more than about 15%....if there are washers then that may affect the torque reading. I would say use a very small ratchet if you dont have a small bicycle sized torque wrench

 

[StarCruiser]

Trouble is, on the 24v engine the injectors are under the rocker cover so leaks can go unnoticed. I tightened mine to the manual on the 12v. It felt as if I was stripping them but I've had them off since and there's been no damage. They are a fine pitch if the same as mine so go round further for the same torque and squash into the washers so again it feels risky but is in fact ok. I've since done mine by hand, although they're easy to get at.

 

[frank rabbets]

The correct figure is 18 Nm. These are banjo bolts for the spill pipe. Unlike most banjo bolts you cannot use the old washer/gasket as they will leak. A leak will cause fuel to go unnoticed into the sump. After fitting keep checking the engine oil level. An increase in oil level = a leak.

I had a leak using old washers but never using new ones.

 

[Allchin]

The thread dia. is 6mm, though there is a neck down to 5mm! In the standard torque tables at 6mm the highest spec bolt is 12Nm in the Toy workshop manual at 18Nm. In fact the actual text says "Hollow screw: 18Nm(176kgf.cm,13 in.lbf). When there is a mistake with the inch lb value, it doesn't bode well for the other values. The line below gives the torque setting for a 12mm nut at 19Nm(where the leakage pipe leaves the head). I have ordered a pressure gauge(could not find mine) and run the leak tests shown in the WM. re-reading the test, it says maintain a pressure of 7psi for 10seconds to check for leaks, originally I thought it meant 'should hold' the pressure for 10 seconds. I had done the test but the pressure kept dropping, using the tyre inflater/gauge, though no leaks could be detected on the banjo's/bolts in question, it probably leaks back through the injectors to the pump. When I get the new pressure gauge I will re-test using a hand pump but I now feel confident that there is no leaks on the banjo's. I need to feel confidant that there are no leaks before putting the rocker cover back on.
Then I can move onto the next job.... rear wheel bearings to inspect and re-pack; Rear diff to re-set(leak from pinion); Front diff to recheck(leaks around the studs); One birfield to change and bearing to check and repack; Repair a small oil weep on a weld of the front axel, which is in a hard to get to place. do a rebuild on the gearbox(the sticky will help to

demystify the procedure). All this has come after a 2year 85Km drive from Prudoe bay, Alaska to Ushuaia in Tierre del Fuego.

Stephen

 

[frank rabbets]

It's important to torque up correctly. The top part of the washer is deformed with this torque and grips the waist of the banjo bolt. Also the injector squared top bites into the bottom washer so that cannot turn. The whole is bonded by the link so the bolt is locked securely. I expect you noticed the old bolts are difficult to unscrew even with a spanner.
Yes I noticed the mistake . It should read 13 ft lb.

If you put some detergent on the banjos you can test for leaks with a constant feed from an airline at the pressure they say. Just for peace of mind. Then when driving first time keep an eye on the oil pressure gauge and stop now and check the oil level is not rising. I had falling oil pressure and 4 litres fuel in the sump!!!! Don't worry though it's unlikely you'll have a leak with new washers.

 

[frank rabbets]

P.S. Please put some feedback on the gearbox sticky. I'd like to correct any shortcomings.

 

[IRLGW]

dry torque and lubed torque are different again...

 

[dellboykev]

when i tightened them i did it to 18nm it is a bit nerve racking and it feels like you are doing them too tight but all mine where fine

 

[Allchin]

Thanks for all the replies. The vacuum gauge arrived today, so tomorrow I will conclude the test. I have 'Gas leak detector' spray which I find easier to apply. I may also increase the torque setting from the 12.5Nm.

Yes, I will give feedback when strip the gearbox down, especially if it leaves small gaps of infomation for the imagination!

 

[frank rabbets]

Yes when you apply the full torque the ally washer flattens out and grips the neck of the banjo bolt which stops it coming undone.