The Good and the Very Bad!!!

It’s a good while since this story started but we’ve had family visiting for the last fortnight (the price of living in Orkney!), and the weather hasn’t been great (price of living in Orkney ?).

Today my son came round and helped me with changing the pistons as I’m not really the right shape for rolling around under the van.

I do have a question for those with more experience....

I’ve rebuilt many engines in the past but must confess to never using a torque wrench. I’ve always just tighten things to what I considered, well tight.

In a desire to do the van right I’ve invested in a torque wrench.

To my question: the stated torque setting for the big end bolts (and the cylinder head) is 6 deNm which is what we’ve tightened them to, but it doesn’t seem very tight.

Any thoughts from any of you with experience?

Thanks

Phill

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I presume that the big end caps have locking tabs, as you don’t want to over tighten otherwise it will tighten the big end shells up, did you smear the big end shells with oil before putting them back ?
But as you say 6nm doesn’t sound a lot, I would have expected it to be in the 20 to 40 range
Keeps us updated on your engine rebuild
 
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I presume that the big end caps have locking tabs, as you don’t want to over tighten otherwise it will tighten the big end shells up, did you smear the big end shells with oil before putting them back ?
But as you say 6nm doesn’t sound a lot, I would have expected it to be in the 20 to 40 range
Keeps us updated on your engine rebuild
It said 6 dNM that’s 60NM.
 
Make sure you hone the bores before fitting new rings as the bore may be slightly oval across the stroke,smear big end shells with grease,oil the bores and pre fill the oil filter before fitting,something i always do.
As yo tighten each big end cap across each bolt we bit at a time make sure the crank moves free,good luck with the build.
 
Yes would echo advise re honing bores , but from the point of getting rid of ridge that will be evident at top of bores where the piston rings have been rubbing to , as the old rings would have worn to suit , the new rings will not be bedded in an could result in broken ring if revved hard . you will need one of these as well as the torque gauge https://www.ebay.co.uk/itm/1-2-Squa...961552?hash=item2a59b99750:g:G1kAAOSwNgxWEpr2
A good workshop manual would be a worthwhile investment , as torques, angles and belt tension settings are all critical for a long life , and cam belt may need checking for tension after running period , although not specified in all belt driven engines. The water pump hasnt been changed in a long while by look of it , so good time to do that job , also check for leaky oil seals as contamination will shorten belt life considerably :)
 
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Yes would echo advise re honing bores , but from the point of getting rid of ridge that will be evident at top of bores where the piston rings have been rubbing to , as the old rings would have worn to suit , the new rings will not be bedded in an could result in broken ring if revved hard . you will need one of these as well as the torque gauge https://www.ebay.co.uk/itm/1-2-Squa...961552?hash=item2a59b99750:g:G1kAAOSwNgxWEpr2
A good workshop manual would be a worthwhile investment , as torques, angles and belt tension settings are all critical for a long life , and cam belt may need checking for tension after running period , although not specified in all belt driven engines. The water pump hasnt been changed in a long while by look of it , so good time to do that job , also check for leaky oil seals as contamination will shorten belt life considerably :)
hi.
i use a tool with lots of carburundum stones on stems like a christmas tree
you put it in a drilling machine and oil it and hone the glaze off the bores
the stems are springy so puts pressure on the stones. works great is cheap
to buy and quick to use.
 
Okey dokey, an update and look for advice...

Slightly long story, sorry.

We got the replacement pistons and cylinder head fitted and all rebuilt, and fire him up.

The engine ran but sounded like a bag of bolts! There was a distinct knock almost like tappet knock. So, I double-checked all the valve clearances, and the valve and injector pump timing and they were all okay.

Small admission at this point. The noise was very similar to a tapping sound that we were hearing before the belt failure (but much louder). The one and only garage/mechanic on Westray said he thought it could be a sticky injector but didn't want to go any further. We tried some injector cleaner on our last trip and were thinking that it had gotten significantly quieter. Then disaster struck!

With this in mind, I took out the injectors, stripped them down and cleaned them all.

Still the same.

Then we made the discovery that you can get different thickness head gaskets for diesel engines. As it happens the one we fitted was 1.7mm and the correct one for the piston protrusion on my engine is 1.95mm. At least nothing was fouling with the 1.75mm gasket but I hoped that it was maybe causing too much compression.

With the correct head gasket in hand, we stripped it all back down again and replaced the head gasket.

Started him up last night and it's exactly the same!

I have uploaded a video of the engine running to YouTube.

Anyone have any thoughts (nice ones please!).

 
Get the injectors checked by a specialist, to make sure they are fuelling and working correctly
Do you know of any that offer a postal service? Part of the problem I face is living where we do (Westray, one of Orkneys Northern isles).
 
sounds like a valve hitting the piston or to thin a head gasket,if you have skimmed the head then use thicker gasket to make up distance,and did you take feller gage gap between pist skirt and bore,could be a bit of slap.
 
When we stripped it down the second time, after suspecting we’d fitted a too thin gasket, there was no evidence of any of the pistons making contact with a valve as there were no marks at all.

We checked the piston protrusion using a dial gauge and they were all within the specified 0.96 - 1.05mm for a 1.95mm gasket so I ordered a new gasket at that thickness.

Never thought to check the piston skirt/bore clearance. Oh my, I don’t want to have to strip it all down again!
 
I would suggest getting the injectors looked at, they can make a loud bang like a noisy tappet if they are on the way out
 
sounds like a valve hitting the piston or to thin a head gasket,if you have skimmed the head then use thicker gasket to make up distance,and did you take feller gage gap between pist skirt and bore,could be a bit of slap.
I would suggest getting the injectors looked at, they can make a loud bang like a noisy tappet if they are on the way out
I’m fancying the injectors myself there’s just nowhere local where I can get them tested.
 
I got some quite cheap on ebay. Perhaps get one and then replace one and see if it makes a difference, if it doesn't move it to the next cylinder and so on.
 
The Bosch Diesel Network site will turn up service centres that
at a guess will do a postal service. Probably wouldn't be wasted
money because you could give them the go ahead to service the
things any way set the spray patterns, ultra sonic clean up
maybe a new nozzle or 2. Saves buying 2nd hand unknowns.
Your eng. sounds sweeter than my 4L Merc. TBH!
 

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