[engine_work] Xu9j4 Mi-16 Rebuild

[kyepan 291]

i missed this aswell!! nearly cost me my block!

Missed what, I don't understand!?!

[kyepan 291]

Quick question - when an oil pump is dry/new, how does it prime?

 

Thinking about how my fishtank pump primes - it takes a while to suck up the fluid by moving air.. then it catches fluid and off it goes.. but this can take some time.

 

Is there any way to help it prime?

 

Thinking about the whole Mi-16 oil system, the filler goes into the sump, instead of across the cams / down the head exit. So.. priming the whole thing is not going to be the easiest procedure. (I realise this is not strictly priming but the cam will be the last thing to get any oil into it / sprayed onto it)

 

also - the books i have been reading, and pretty much everything online i have been reading keeps harping on about chamfering the new bearings and journals with a bearing scraper....

 

but none of them really explain why? my guess is..

 

A) remove any imperfections around the edges of the bearing that are raised and so likely to cut into the journals.

radiuses flow better than edges, so the oil will release better into the space around the edge of the journal.

 

these are both guesses.. anyone?

Edited November 28, 2011 by kyepan

[wicked 103 3 Cars]

Take the pump and put it in the sump and add 4 liter of oil..... and search for air in the pump ;-)

 

But it will take some time before all bearings have oil pressure.

Therefore, use assembly lube and crank it without spark plugs, until you have some pressure.

Edited November 28, 2011 by wicked

[Paul_13 212 1 Cars]

Just put some assembly lube on the cams mate. When the mineral reaches the cams the lube will dissolve.

 

As for priming the pump, just have a healthy battery and cross the terminals on the starter with ignition off (obviously with oil in the engine). Allow it to turn over many times, giving the starter a break now and again. You may see a little bit of pressure on the gauge.

[welshpug 1,621]

the o.e bearings I fitted were radiused;

 

 

 

 

Assembly lube + plugs out + good battery, touch of oil down the bores if it has sat fore a while between fitting the rings and firing up.

[kyepan 291]

This evening i have been plastigauging the mains.. and have a question.

 

So the Haynes gives some values in the table, and I have looked them up on here, people like to quote the Haynes which does worry me a bit, however on page 2c.19 it also says.

 

"Note that Peugeot, do not specify a main bearing running clearance for the 1905cc engines, the figure given in the specifications is a guide figure which is typical for this type of engine, on these engines therefore always refer to your peugeot for your correct running clearance before condemning the component concerned"

 

0.025-0.05mm mine are 0.063mm across the board.

 

XU10 engines quote up to 0.69...

 

The crank was checked and polished, bearings were supplied with the polish..

 

I've mic'd the crank and it is 59.98mm (factory is 60, regrind is 59.7), and the bearings are 1.82, which is bang on for the Pug rebuild manual.

 

My plan is to whip the crank out, torque the caps back down with the bearings in and use the bore gauge to get a reading on the actual ID.. but all that will ultimately do is either tally up with the plastigauge or not.

 

some reading.

Edited November 28, 2011 by kyepan

[kyepan 291]

another link

 

Max clearance should be 0.01 inch per inch diameter.

50mm in inches = 1.96850394

60mm in inches = 2.36220472

 

1.96850394 * 0.01 = 0.00196 inches clearance = 0.049784 mm maximum clearance for a 50mm journal

 

 

2.36220472 * 0.01 = 0.00236 inches clearance = 0.059994 mm maximum clearance for a 60mm journal.

 

So my reading is less far off it then says + 0.005inches for race / higher viscosity oil = 0.073mm

[kyepan 291]

Also thinking about it... perhaps that's why the xu10 runs a 2 bar spring, hence being able to run a bit more clearance...I've checked and they use the same oil as the 1.9 so that must account for the difference in the bearing clearance, other than operating temp

[kyepan 291]

That was definitely worth it.. mic-ing up the crank on each journal, initially i was getting 60 plus mm, then if i kept fiddling, it started dropping to 59.99 or 98, and the odd 97. I took an average across each journal. Then setting the micrometer to 60.00 allowed and zeroing the bore gauge, allowed me to take a measurement of each journal at vertical, right 30 deg, and left 30 deg. Results are interesting.

 

5 journal size 59.98 average

5 vertical ID 60.04 = 0.06 mm clearance.

5 right ID 60.048 = 0.068

5 left ID 60.06 = 0.08

 

4 journal size 59.99 average

4 vertical ID 60.04 = 0.05 mm clearance

4 right ID 60.04 = 0.05

4 left ID 60.06 = 0.07

 

3 journal size 59.99 average

3 vertical ID 60.034 = 0.046 mm clearance

3 right ID 60.033 = 0.044

3 left ID 60.055 = 0.56

 

Struggled to get a good reading on 2 and 1 as the bore gauge was fouling on other objects, perhaps i need to remove block from stand and access from other direction.

 

2 journal size 59.99

2 vertical ID 60.045 = 0.055 mm clearance

2 right ID 60.04 = 0.06

2 left ID 60.35 = 0.065

 

Ran out of time to take off stand mount and do bearing 1.

 

May try swapping 5 and three bearing shells to see if i can even it up a little. But that is a lot more like it, Also noted the part numbers of the original shells are marked up differently to mine.

 

Cheers

 

J

 

ps, despite being incredibly gentle, i don't like the way the bore gauge is marking the shells.. i bonked one, and may have left a small mark on it.. que swearing, but it's not feel able with the nail..so.

Edited November 29, 2011 by kyepan

[kyepan 291]

Word of note to other new engine builders... you are NOT supposed to stick the bore gauge inside the mains with the bearings in them..... new set of bearings on order.

 

You are supposed to measure the journals, then the shells with a micrometer with spherical ends, then the inside diameter of the properly torqued mains sans bearings with a bore gauge.

 

if you don't you'll just ruin the surface of your new bearings.

 

*slaps palm against forehead for being an idiot.

 

 

 

J

[Paul_13 212 1 Cars]

O dear

 

IDIOT!

[kyepan 291]

this evening we put the pistons in the liners..

three done

 

lubing the bores.. with lube... arf

 

guiding the rod into the liner with the compressor on.

 

gentle tap into the liner with the butt of the handle.

 

4 done

 

 

then put the spray bars in threadlocked and torqued them up.

 

cheers

 

J

[kyepan 291]

New bearings will be here by the weekend, so will continue the build on monday, an assemble the bottom end.

 

A question, Paul and i have been discussing how to check each piston is moving freely when it's attached to the crank.

 

Now.. in an iron block, simply install each one, rotate crank and check.

 

However.. This being a floating liner block means the situation is more complex. Because the liners will just lift off the seats. So I either have to go to the trouble of:

 

1) install a liner and connect bottom end.

2) hold liner down with washers / bolts

3) rotate crank and check for binding

4) remove washers to allow next liner

5) hold both liners down.

 

Repeat 4 & 5 for other liners.

 

I guess i could cut down a few of the old head bolts to allow us to do this... I want to make sure the assembly is rotating freely, and do that in a methodical way..

 

J

[Tom Fenton 1,524]

Personally I would have installed the liners to the block, clamped them in, and then fitted each rod and piston, plastigauge each one, if the plastigauge clearance is in spec and even across the shell width then it should turn fine, just tighten down each one in turn, if it turns over OK then move onto the next, if it goes tight you will therefore know it was the last one you tightened down that is the culprit.

[kyepan 291]

Personally I would have installed the liners to the block, clamped them in, and then fitted each rod and piston, plastigauge each one, if the plastigauge clearance is in spec and even across the shell width then it should turn fine, just tighten down each one in turn, if it turns over OK then move onto the next, if it goes tight you will therefore know it was the last one you tightened down that is the culprit.

that makes sense as an alternate approach. thanks for the reply.

[petert 549]

I think you're making it harder than it needs to be. Once the liners are in the block they should be clamped down (old head bolts, large washers etc.). Then all you're worried about is the rod bearing clearance. Just make sure they're sitting perpendicular to the crank then torque them up with some plastigauge. It's far easier to do this step with the crank on the bench and the rod without a piston on it. If clearance isn't correct you don't have to pull the bottom end apart again.

 

In regards to fitting pistons,next time buy a tapered ring compressor like these: http://www.mxsouth.com/wiseco/wiseco-miscellaneous-engine-items-tapered-ring-compressor-sleeves.htm

 

I use an old liner which I've cut down (top third) and turned a slight taper inside it.

 

Far better to fit the piston from bottom of the liner, whilst supporting the rod in your hand. There is a small taper at the bottom of the liner which helps start the rings.

Edited December 2, 2011 by petert

[kyepan 291]

Thanks for the advice peter

[kyepan 291]

New bearings have arrived, also some fresh plastigauge should be with me later, going to clamp the liners down as per above.

[kyepan 291]

This evening, Paul and I did the following.

 

Installed new bearings (they look way better than the old ones) Plastigauged them, swapped the shells over to equalise the clearance.

 

They are all around 0.060mm now.

 

Lubed the shells, installed the crank.

 

Installed the hockey stick seals, with a touch of silicone sealant, installed the thrust washers, checked for float which was 0.010mm both sides.

 

Then went to rotate the assembly, it moved smoothly with a gentle turn of the wrist until... bonk, it fouled on the bent spray bar.

Out came the spray bar, gently bent back into shape and trial fitted a couple of times, bent a wee but more, and fitted, crank rotated fine.

 

Tomorrow liners, big ends etc.

 

Cheers

J

[kyepan 291]

This evening we got the bottom end assembled, and i am very pleased with the results.

 

Despite the above advice, we put the liners in one by one, because the washers we had to camp the liners down would have fouled on the piston ring compressor.

 

So we followed the following process.

 

Put O ring on liner oiled,

 

Take off big end cap

 

Put top shell in

 

Slide liner in it's place, and orientated as per liner protruderance checks earlier.

 

Clamp liner down gently with some paper under the washer so it doesn't mark the liner top.

 

rotate engine on stand,

 

Put plastigauge onto big end journal

 

Torque it up, and then take it off to measure journal.

 

Clean up cap and journal

 

Drop piston down

 

lube journal

 

Nip it up..

 

Rotate crank to check it's all good and rotating freely

Repeat for liner 3

 

 

liner 2

 

 

and 1.

 

Then you have a set of bearing clearances..

 

4 - 0.035mm

3 - 0.030mm

2 - 0.027mm

1 - 0.033mm

 

Then swapped the top shells of the widest and the tightest (2-3) to even them up a bit. Maximum variance across all of them was 0.007.. so that's was alright to begin with. certainly well within the 0.025-0.050 Haynes spec.

 

After that, torqued them all up and checked how much force to rotate.

The only decent use i can find for a 50 Cent cd...

 

A question, roughly how many foot pounds / newton meters should a fresh four pot bottom end take to turn (I realise this changes as you reach piston BDC/TDC) over? Just so i have an indication.

 

bottom end nearly done

 

May look at the oil pump tomorrow night, and possibly the end plate.

 

Again thanks to Paul, who supplied the washers and tube to hold the liners in, plus help generally, and advice.

 

Cheers

J

Edited December 8, 2011 by kyepan

[kyepan 291]

A quick post on the crank assembly.

 

some reading

 

It was balanced by Alan snowdon of Vibration free in oxfordshire.

 

Intial

Crank LH (pulley) 6.1g

Crank RH (flywheel) 1.8g

Flywheel 6.2g

Clutch 4.1g

pulley 2.3g

 

Final

Crank LH (pulley) 0.14g

Crank RH (flywheel) 0.19g

Flywheel 0.118g

Clutch 0.21g

pulley 0.09g

 

 

F (kg) = 0.01 x W x R X (rpm / 1000)squared

 

W = imbalance mass in grams

R = radius in cm guessing 10cm is radius of rotating crank

 

0.01 * 0.014 * 10 * (( 7500 /1000)* (7500 / 1000))

 

0.0014 * 56.25 = 0.07975 kgs @ 7500 rpm

 

Although I don't know the distance from the centerline to calculate the gmm

 

if somone else could help with this maths as i don't quite understand if both imbalances need to be added together?

 

 

even if it was 100mm that would still be 0.019+0.014 = 0.033 * 100 = 3.3gmm

Cheers

 

J

Edited December 10, 2011 by kyepan

[kyepan 291]

Found this

 

In my box of bits I got with the gti6 sump... So slight change of plan. Get a new 52 tooth chain for it , and run a full xu10 oil setup. That way I'll feel better about the slightly larger big end clearances. Will delay the build by a couple of days but heh...

 

1033 10 01 OIL PUMP CHAIN - INJECTION XU10J4 - 52 LINKS - to be ordered tomorrow.

 

Cheers

J

[kyepan 291]

new chain ordered, here weds.

 

Cleaned up the water dist block / thermostat housing, crank end plate ready to go on.

 

And put on the water pump, sans one bolt that i tried to clean the threads on with the wrong die.. ruining it.

 

Head going on tonight, hopefully.

 

Cheers

 

J

[kyepan 291]

This evening we bolted the head on... That's about it really.

 

Here is a photo.

 

So just waiting for the chain. And then the pump sprocket and pulley can go on.. Water dust block etc.

 

Here's another photo.. Just in case you didn't see the first photo.

 

Cheers

 

j

[Paul_13 212 1 Cars]

We did a bit more tonight

 

 

 

 

 

Bastard beat me to it

Edited December 12, 2011 by Paul_13