[engine_work] Xu9j4 Mi-16 Rebuild

[kyepan 291]

yesterday evening i got the crank pulley undone using the block of wood technique, was going to take the head off, but only had an hour so i removed the crank pulley, cleaned it up, bagged and tagged. Also removed most of the bolts holding on the thermostat housing, one of the hex bolts is very badly rounded, so i'll need another from somewhere, perhaps i may use the thermostat housing from the engine in the car.

 

This is the broken tab that the crank pulley locking pin goes in between... so this is the bit i need. anyone with one spare, please shout.

 

Also have a look down the throats of the inlet ports on the head, do the guides look like they've had work on them? or the throats themselves?. That's quite a sharp edge where they split.

[kyepan 291]

yesterday evening i got the crank pulley undone using the block of wood technique, was going to take the head off, but only had an hour so i removed the crank pulley, cleaned it up, bagged and tagged. Also removed most of the bolts holding on the thermostat housing, one of the hex bolts is very badly rounded, so i'll need another from somewhere, perhaps i may use the thermostat housing from the engine in the car.

 

This is the broken tab that the crank pulley locking pin goes in between... so this is the bit i need. anyone with one spare, please shout.

 

Also have a look down the throats of the inlet ports on the head, do the guides look like they've had work on them? or the throats themselves?. That's quite a sharp edge where they split.

[petert 587]

Ports have definitely been massaged. Guides look original, but it's the fit inside that counts, not the outside appearance. If worn, it's impossible to cut concentric seats and valves will struggle to seal properly.

[kyepan 291]

Ports have definitely been massaged. Guides look original, but it's the fit inside that counts, not the outside appearance. If worn, it's impossible to cut concentric seats and valves will struggle to seal properly.

so measurement of wear on the guides in important then, that's one of the measurements on my list, is the internal measurement on a micrometer small enough to do that?

[welshpug 1,657]

I do believe you'd drop the valves off the seat and measure the side to side movement with a dial gauge against the side of the valve head.

[James_m 0]

405 1.9 mi16, "HSG gasket plate", part #0514 81 it would seem. 0514 57 for a 2.0 XU10J4.

 

Strangely i broke mine on my XU9J4 and found the XU10J4 part to be identical and fit with no problems.

Who knows with Peugeot's weird and wonderful parts catalogue

[kyepan 291]

Strangely i broke mine on my XU9J4 and found the XU10J4 part to be identical and fit with no problems.

Who knows with Peugeot's weird and wonderful parts catalogue

that does not suprise me!

 

today we (ant and i) stripped the engine down, and on the whole it would appear to be in very good condition.

 

Liners were fairly new, not lipped, but there was some corrosion because the engine had been standing, these need honing.

Pistons also looked very new, not much carbon, standard though

waterways were very corroded, with lots of scale, it would seem the car has been run on water and not kept full of coolant.

Water pump was shagged for the same reason.

Head came off, could not tell if it already had three angle valve seats, will strip the head later.

Big end bearings looked in very good

However the main bearings had picked up a bit, one noticable mark on the crank, but on the whole not bad.

 

Only took a couple of hours.

[kyepan 291]

Quick question, measured one of the bores last night and came back with a fairly even reading of 83.5mm

 

There are still light honing marks on the area that doesn't see piston contact..which also measures 83.5

 

So am i correct in thinking that either.

 

1) i am measuring it wrong with the bore gauge.

 

process i used, was to set the bore gauge against the micrometer, zero it so it can expand and give a reading. then pop it in the bore and check the different at different heights and rotations.

 

2) the liners have been overbored by .5mm

 

what do you guys think?

 

Cheers

 

J

[welshpug 1,657]

any markings on the piston crowns? the ones I have here have a tolerance grade indicated by a letter stamped into them

[kyepan 291]

any markings on the piston crowns? the ones I have here have a tolerance grade indicated by a letter stamped into them

i'll have a look see tonight.. do you know what letter indicates what grade, or is that something the rebuild manual?

[DrSarty 90 1 Cars]

I'll go out on a limb: overbore.

 

You know me J, (no expert), but 0.5mm is a lot in engine terms surely? Manufacturing tolerances would surely be a lot tighter than that on such a component. I'm sure you can measure accurately, so perhaps these are 83.5mm liners?

 

But as WP suggested, the answer will probably lie in the piston markings as it will indicate what's been used to fit into your liners.

[kyepan 291]

I'll go out on a limb: overbore.

 

You know me J, (no expert), but 0.5mm is a lot in engine terms surely? Manufacturing tolerances would surely be a lot tighter than that on such a component. I'm sure you can measure accurately, so perhaps these are 83.5mm liners?

 

But as WP suggested, the answer will probably lie in the piston markings as it will indicate what's been used to fit into your liners.

tolerance is probably more like a tenth of that 0.05mm or something like that, so yes if i've been using the measuring stick right, it's too much to be wear.

 

Trying to find out if standard oversized pistons are available, or if they are likely to be forged items, Anthony didn't seem to yelp with excitement when we took them out.. So i'm guessing they may have been standard items.

 

I did search, but only seemed to come up with references to forged items.

[petert 587]

If they have an X or a Z in the crown they're a standard 83.00mm piston, indicating their deck height measurement. Further, if standard, they'll have either A, B or C stamped in them indicating their toleranced size. A being the smallest piston, C being the largest.

[kyepan 291]

If they have an X or a Z in the crown they're a standard 83.00mm piston, indicating their deck height measurement. Further, if standard, they'll have either A, B or C stamped in them indicating their toleranced size. A being the smallest piston, C being the largest.

thanks peter, i've got propper digital verneirs now to check this out.

 

this evening i've continued stripping the head, cams came out last night, and tonight i tried to use the valve spring compressor for the first time, it's too small and doesn't make it round the head casting. clearly it's for little engines with vertical valves like minis....

 

slightly concerned about the state of the inlet cam, it has some surface rust. The cam journals are in general fairly good. two points i need to raise, i'll put photos up later.

 

Inlet cam, belt end, journal number five (so the first one) looks quite badly damaged for 1/4 of the journal surface, it looks like a much less knackered version of my ex's 323 that welded the cam shaft into the journal.

 

also exhaust cam journal at flywheel end journal number one has picked up along one line, it looks ok othewise.

 

Depending on the quality of the photos, does this mean the head is scrap, or can the raised sections be flattened off with some gentle polishing?

 

Also if anyone has a spring compressor suitable that i could borrow or buy, please yell.

 

cheers

 

j

[Paul_13 212 1 Cars]

Yelled in the form of a text

 

Get a socket, amd use a hammer to free off the collets they can get stuck.

Edited July 2, 2010 by Paul_13

[kyepan 291]

link to photos

 

photos of the bearing surface... for your consideration.

 

 

 

 

 

 

 

 

and the other one that has picked up.

 

the head has had some light work to the throats and valve stems, would like to know if it is scrap, or what my options are.

 

cheers justin

[Anthony 1,003]

I'd personally say that should be fine, as there's plenty of "good" journal surface there - just make sure that there's no high points on the scored area, or if there is, remove them with a bit of emery or something.

 

My valve spring compressor is still on loan to someone on the forum, but when I get it back, you're welcome to borrow it

[Paul_13 212 1 Cars]

It's alright Anthony he's borrowed mine

[kyepan 291]

Quick question, despite searching fairly hard, i can't find out what people (generally DrS) soak lifters in.... is it carb cleaner, and if so how long and what depth does the liquid need to be. Then... why do you bang the centers out again? i can understand refacing the surface but not the removal of the Center thing.

 

I remember a post to some video clips, but can't for the life of me find it... I even used Google search, name search.... etc, it must have got archived or something.

[welshpug 1,657]

http://www.taylor-eng.com/16v_head/16v_head.htm

 

Bookmark Library FTW

[kyepan 291]

http://www.taylor-eng.com/16v_head/16v_head.htm

 

Bookmark Library FTW

brill thanks! i knew i had read that before!

[kyepan 291]

Today the head went to Paul Gardias for some work, nice chap, very welcoming.

 

He immediately spotted it needed welding, due to corrosion, and was blowing on one cylinder. he also commented that the corrosion on the head showed it had been run without coolant. The corrosion then expanded and pushed the head away from the block. Keep your coolant ratios correct sports fans.

 

 

We discussed the damaged journal, and worst case, he would line bore it. We also discussed valve springs, as mine are of varying length, so tonight i'll be measuring them for your reading pleasure, un compressed. If anyone knows how to measure them in a compressed state i would be interested.

 

so a photo... here are the springs, lifters, collets etc..

 

 

and then the service manual...

 

d1 is the uncompressed

d2 is compressed

 

what are p1 and p2?

 

d1 : mm = 38.8.... i'm over a centimeter out... wtf?

 

all measured against d1

 

Inlet valve spring 1 = 46.8 mm

Inlet valve spring 2 = 46.8 mm

Inlet valve spring 3 = 47.66 mm

Inlet valve spring 4 = 47.23 mm

Inlet valve spring 5 = 47.37 mm

Inlet valve spring 6 = 46.42 mm

Inlet valve spring 7 = 46.73 mm

Inlet valve spring 8 = 46.49 mm

 

Exhaust valve spring 1 = 47.82 mm

Exhaust valve spring 2 = 46.73 mm

Exhaust valve spring 3 = 46.52 mm

Exhaust valve spring 4 = 46.81 mm

Exhaust valve spring 5 = 46.63 mm

Exhaust valve spring 6 = 46.76 mm

Exhaust valve spring 7 = 46.62 mm

Exhaust valve spring 8 = 46.9 mm

 

also the variance is over a mm, and some of the valves have thicker washers.

 

thin washers on all but inlet 2 & 3 are 0.63mm

inlet 2 is 1.12mm

inlet 3 is 1.09mm

 

any knowledgable heads know why my springs are a cm longer, and why some washers might be different?

 

edit - think i've just figured it out.. p1 and p2 are the number of newtons applied to check... probably in preload state and compressed state, correct?

 

cheers

 

J

Edited July 10, 2010 by kyepan

[welshpug 1,657]

My understanding would be as follows;

 

P1 is DaNm of force applied.

 

D1 the resulting spring length.

 

P2, DaNm of force applied,

 

D2 resulting length of spring.

 

edit, missed your edit

 

The shims would be to compensate for varying valve seat heights to give the same compressed height of the springs.

Edited July 10, 2010 by welshpug

[kyepan 291]

had a read of this and now understand.... thanks welshpug.

 

need to find a spring tester though..

[petert 587]

38.8mm is the installed height. 29.6mm is the compressed height. ie 38.8 - 9.2 (std. lift) = 29.6

 

I'd just put an extra shim under each spring. That usually puts them back in spec. after a long life and rebuild. I've tested many springs.