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PollyMobiles Rebuild

my job workload is just non-stop long hours and god knows when I'll have time to work on the car.

for now lets measure the condition of the stock engine

DSC08442.JPG


measured the bores and the upper sections abit oval but the average bore diameters from 71.02 - 71.07mm

the max standard bore dia is 71.03mm so this block has had it :(

dq7.gif


measuring the piston ring end gaps are no better. inserted the oil rings and look at that 1-2mm gap!

DSC08443.JPG


end gaps measure (top, 2nd, oil1, oil2)
cyl1: 0.457 , n/a , n/a , n/a
cyl2: 0.432 , n/a , n/a , n/a
cyl3: 0.457 , n/a , n/a , n/a
cyl4: 0.457 , n/a , n/a , n/a

all of the gaps are beyond the 0.635mm my feeler gauges can read :/

the piston skirt dia and piston-to-bore gap are
cyl1: 70.93 , 0.104mm
cyl2: 70.91 , 0.125mm
cyl3: 70.93 , 0.108mm
cyl4: 70.91 , 0.124mm

the max piston-to-bore gap is 0.03mm!

also measured the oil ring tension drag with abit of wd40:
cyl1: 3.5kg
cyl2: 4.25kg
cyl3: 3.5kg
cyl4: 4.0kg

well I believe I can conclude that this stock engine is utterly worn and not worth building :oops:

so it's all down to this new rebuilt forged engine and I've got no spare engines.
 
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this morning I've been experimenting on trying to stretch the oil expanders to increase tension.
frank how did you do it?

pulling it apart in a straight line will just deforms it and I'd have to reshape it into a circle again, tedious & inconsistant.

wrapped it round an aerosol can and tried to pinch the ends closer with some thin pliers but there's alot of friction and its quite a stiff spring (also the standard & forged ring expanders wavyness are defferent).
although just pinching it slightly has increased the drag from 4.25 to 5kg so it has worked. just requires incremental tweaking similar to gapping the rings.
 
just pulled it straight paul, then crudely reformed the circle :) you usually have to hold the 2 ends down while fitting the rings tho (to stop them overlapping)
 
h701micra said:
What's the plan with this worn out engine then paul?
Click to expand...
l_jonez said:
No, it's now prefect for a corsa piston build!
Click to expand...

so I have two engines in the garage.
Engine1 was the old incorrectly over-bored forged block so its broken.
Engine2 that was the grey micras original stock engine with broken ringland is worn beyond standard spec.

I have decided to just scrap the two engines for however many quid I'll get back cos:
  • no point in extra time, money & effort making a corsa piston engine cos I already have a low compression JE forged piston engine
  • the cost of remachining & rebuilding Engine2's block if the forged engine fails catastrophically would be uneconomical and could just buy another stock engine for that amount.
  • since the blocks and pistons are totally worn, I'm certain that the rest of the major parts are the same condition thus no value in keeping em. I will be keeping the little valuable reusable bits like valve shims, sensors, fixtures.
  • the two useless engines are wasting garage space.
  • if the forged engine does fail one day and uneconomical to rebuild, then I'd just buy a used working standard 1.3 engine off ebay from £100, bang it on and run the turbo map for a stock engine.
two engines ready for the scrappers

DSC08444.JPG
 
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I ask because I was wondering if I could have one? Of course they are of no use to me but I wanted to compare bits n pieces with the ga16. See what can swapped over for any gain or improvement :)
Plus parts/spares etc are scarce for the GA lump. Plus if any parts are useful to a CG then what few parts are available will be cheap :)
 
since karl's interested in the head for his turbo project and h701 interested in the engine for spares, I'll list whats missing or worn in the engines to my rough memory. they are bare btw so no outer attached bits

Engine1
  • no valve shims
  • no inlet/exhaust studs
  • old forged engine block is over-bored too much
  • few missing bolts
  • pistons, crank & bearings unknown condition
Engine2
  • broken rocker cover
  • no valve shims
  • no inlet/exhaust studs
  • pistons, rings, bores worn beyond spec
  • piston #3 broken
  • few missing bolts
both the heads, crank, cams are fine I think.

karl which exact bits do you need? I can sell u the bare head with cams (no shims, studs or cover) for bout £70 delivered?

h701 if ur still ok with buying the engines as I've listed above, I can sell either of the bare engines for bout £80 but cos of their weight, I'm not sure if any courier will accept nor economically deliver it, unless you come pick it up one weekend?
 
so since I've now found that this stock engine was actually well and truly worn out, maybe the big end gaps could've caused blowby/slight oil burn which could've affected the turbo setups MOT emissions? although the stock setup with the cat passed fine.

although this rebuilt forged engine will run tighter ring clearances and once I've fixed the loose oil rings, I dunno if it could pass with the relatively new standard catalyst I brought last yr.
wonder if there's a much more efficient cat, will I need to relocate/reweld it closer up the turbo downpipe, and if it's worth the extra few hundred quid?

or I should prob just save the pennys n continue swapping over to stock setup each mot year?
 
frank said:
blowby will only raise the HC tho surely paul ?
Click to expand...

yea the turbos CO2 and HC was all over the place.
at my cousins using his gas machine, when the cat was really hot enough, there was a very fine tuning window between too much CO2 and too much HC.
but at the MOT they only had afew secs to heat it up therefore the cat didn't get hot and didn't do enough to reduce the levels.
suppose the bad end gaps didn't help.
hence my doubt as to whether the turbo will ever pass MOT.
 
the turbo itself does,nt have any effect on the emissions tho eh paul, its just a minor obstruction in the exhaust (and not creating any boost @ 3k in neutral)
its just the fact that the cat is further away from the stock position :)
mine flew through with a high mile engine and nistune and 2.0 injectors fitted
 
frank said:
the turbo itself does,nt have any effect on the emissions tho eh paul, its just a minor obstruction in the exhaust (and not creating any boost @ 3k in neutral)
its just the fact that the cat is further away from the stock position :)
mine flew through with a high mile engine and nistune and 2.0 injectors fitted
Click to expand...

I meant the very worn bores n rings of the stock engine might have had an effect on emissions plus fact that the secondary cat is too far away to have much cleaning effect hence doubting if my turbo setup could pass.
but I dunno, maybe this tighter forged engine might burn cleaner maybe not?
 
pollyp said:
since karl's interested in the head for his turbo project and h701 interested in the engine for spares, I'll list whats missing or worn in the engines to my rough memory. they are bare btw so no outer attached bits

Engine1
  • no valve shims
  • no inlet/exhaust studs
  • old forged engine block is over-bored too much
  • few missing bolts
  • pistons, crank & bearings unknown condition
Engine2
  • broken rocker cover
  • no valve shims
  • no inlet/exhaust studs
  • pistons, rings, bores worn beyond spec
  • piston #3 broken
  • few missing bolts

h701 if ur still ok with buying the engines as I've listed above, I can sell either of the bare engines for bout £80 but cos of their weight, I'm not sure if any courier will accept nor economically deliver it, unless you come pick it up one weekend?
Click to expand...
I'll probably pick it up one weekend. It doesn't need to work or be complete just enough that I can have at major components and see what's comparable.
However if any others are interested in parts such as karl then I'm quite happy to take the remains of either engine
As a reference engines can be delivered but at around £50
 
h701micra said:
I'll probably pick it up one weekend. It doesn't need to work or be complete just enough that I can have at major components and see what's comparable.
However if any others are interested in parts such as karl then I'm quite happy to take the remains of either engine
As a reference engines can be delivered but at around £50
Click to expand...

if karl requires the head out off one engine, you still have all of the other engine. I'll try keep em in storage for another week suppose.

would that £50 be just for the delivery itself on top of the £80 for the engine? hence mentioning it might've been uneconomical to post, especially if ur never gonna use it. collecting it urself may end up cheaper than the postman. i'll get the cuppa on :p
 
I was thinking incase anyone else wanted anything before I got round to fetching it :)
Yea its on top of the 80. Just thought I'd throw it out there as a reference.
Definitely get the kettle on. Be good to meant the troublesome forged turbo build :p
More likely to get here in one piece if I fetch it too
 
h701micra said:
I was thinking incase anyone else wanted anything before I got round to fetching it :)
Yea its on top of the 80. Just thought I'd throw it out there as a reference.
Definitely get the kettle on. Be good to meant the troublesome forged turbo build :p
More likely to get here in one piece if I fetch it too
Click to expand...

I'll try to keep one of em intact for you. so £80 for the engine ok?
good to be aware of the delivery cost.

that over-bored block was left over from the forged project and doubt it can be used, the rest of the engines bits are stock so should be ok for referencing.

indeed you'll be able to bring it home intact and on the same day and we have a chat over a cuppa :) also saves me from a load of hassle packaging and waiting for the engine to be collected by postman.
 
Nothing worse than being stuck waiting for a postman.
Pricewise I'll get saving unless its up for discussion on the day.
At worst I'll knock you down on your tea making ability :p plus I'm only binning it when I'm done
Depending on when I get it depends if you see my K10 or a conked put xsara picasso :D
 
h701micra said:
Nothing worse than being stuck waiting for a postman.
Pricewise I'll get saving unless its up for discussion on the day.
At worst I'll knock you down on your tea making ability :p plus I'm only binning it when I'm done
Depending on when I get it depends if you see my K10 or a conked put xsara picasso :D
Click to expand...

I'll store the engine away ready for you to pickup. £80 is what I'm after
 
Paul did you use a local machine shop to get the block rebored? Just the one we use at work says he wont deck blocks :( lol
 
for stuff that small relative to the weight of the wheel/hub itself, just stick to cheaper stronger safer steel nuts cos the extra cost and tiny weight saving and weaker threads of alloy nuts ain't worth it.
 
But what ahhh. So alloy ones are weaker but Paul's running them. I wanted to buy some so I think I worrying about going round a corner and the wheels come off haha. So what still confused sorry guys.
 

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