Deleting oilsquirters on a mi16

[Tom Rallye 3 1 Cars]

Been searching the topics but cant find a definite answer.

Is it possible to delete the oilsquirters on a mi16 wich  will be made to run NA maximum 6800 rpm?

The reason I ask this is because they seem to have been "machined" on the block that my mechanic is rebuilding for me now and he would like to delete them to avoid oilpressure problems.

Can that be done or will that result in other problems / wear?

[petert 549]

I suppose you could, making it the same as an 8V block. Mi16 pistons usually wear very well compared to 8V, thanks to their oiling however.

Edited May 30, 2018 by petert

[Tom Fenton 1,524]

Not sure why you feel the need to do away with them, I'd leave them in.

[welshpug 1,621]

indeed, I had been wondering if it was possible to machine seats and tap into the oil galleries in an 8v or xu7 block to add them!

[Tom Rallye 3 1 Cars]

He wants to eliminate every possibility for an oilpressureloss. It was running 0.5 bar on idle and 3 on 5000rpm when it was warm before we took it apart.

The pressurevalve of the oilpump (the thing that regulates the pressure of the pump when the oil is getting warm, don't know how it's called in English) was blocked in the open position by the grit. Whe think that caused the low pressure, but he's not sure because he changed the pump and it wasn't much better. That was before we knew about the grit though, so the new pump had to suffer a bit from the grit to.

He just wants to be sure before he puts it all back together...

[Thijs_Rallye 86 4 Cars]

No, don't leave them out, they are there to cool the piston crown and have been put there for a reason. The pumps that have seen grit should be scrapped imho.

 

What crank sprocket are you using? (22t?)

 

I personally would use a 2.0t / TD oil pump if you are going to oversize. Make sure to use an 18t 8v sprocket then.

[Tom Rallye 3 1 Cars]

The pump will be an rfs pump.

I think you also know Joris VG, he's putting it together. I guess he will know wich sprocket to use.

[Thijs_Rallye 86 4 Cars]

I do know Joris. I never had an RFS pump in my hands myself so I can't say if it pumps more volume. Only thing I have is my own recent experience with using an XU10J2TE pump on my own 8v with low oil pressure at idle. An Mi normally has the 22t sprocket, an 8v the 18t.

 

How do your lifter pockets look? If those are scratched by the grit I'm afraid you will lose much (if not too much) pressure there.

[Tom Rallye 3 1 Cars]

The lifterpockets are badly scratched but Joris doesn't think that it loses pressure through there. He thinks they only have to be able to move free and that the scratches don't affect the oilpressure.

Edited May 30, 2018 by Tom Rallye

[petert 549]

Don't you fit a bigger sprocket on the crank to make the pump spin faster and thus improve oil pressure at idle?

[Thijs_Rallye 86 4 Cars]

11 hours ago, Tom Rallye said:

The lifterpockets are badly scratched but Joris doesn't think that it loses pressure through there. He thinks they only have to be able to move free and that the scratches don't affect the oilpressure.

 

Well, if you take a look at this cross section you might reconsider that thought. The lifters are fed oil via the side of the bucket. Same as with electric current the oil will take the path of least resistance. 

 

Could you post a picture of the pockets? If they are really badly scratched it might be a better option to either take your losses with the head or convert it to solid (mechanical) lifters with an appropriate cam.

Edited May 31, 2018 by Thijs_Rallye
Additional thoughts

[Tom Rallye 3 1 Cars]

I only have a picture of the tappet. These were new Febi aftermarket ones. I'm going to replace them with refurbished OEM ones now. The metal of these tappets isn't hard enough. You could already see dimples where the camshaft touched them (could also be caused by the grit that was between the tappets and the pockets and blocked them, but nevertheless...).

You can easily scar these tappets on the side with a screwdriver.

[Thijs_Rallye 86 4 Cars]

This I've already seen on the .nl forum. I fear the worst for the much softer aluminium though. If the case hardened lifters have this kind of damage I can only imagine how the bores must look :(.

 

If the bores look as bad as the lifters I'd either replace the head with another one or convert to solid lifters and corresponding camshafts. (and restricting the oil flow to the head) It all remains guessing judging from these pictures though. Let's hope for the best.

[Tom Rallye 3 1 Cars]

I've got a spare head on the shelf, so wouldn't be a big problem.

[petert 549]

Use it then and save the stuffed head for solid lifters. You can buy 32.5 or 33mm buckets.