Here is what you do:

Take the oil pan off and take a rod cap off to check the health of bearing/rods. If they are unhealthy then ditch the whole project. A NT laser is not worth it.

sacrileger said:

thanks for the suggestion. so true. leak down test wasnt even on my radar. i am still stuck on the old fashion cranking to check compression.

this is a question (not contention) to get better understanding:
what type of result would i get if i left the cams and timing belt on and started with piston #1 at compression cycle TDC - essentially ensuring that all four valves on cyl #1 are closed (rocker arms free to move) and checked for % leakage. then rotate the crank to position piston #2 at tdc, check for leakage, and so on. and then compare the % difference between each cylinder.
the reason why, at least in my mind, it would appear to work is that from my observations when i check cylinders for damage and/or roundness, the problems are typically found at the top, not bottom of the cylinder; perhaps because that's where most of the pressure and work is concentrated. so my thinking goes in favour of having to check for leakage in each cylinder while the piston is at tdc because that's the place where i would lose the most pressure, right at the top. w/o the cams and belt, i wouldnt know where the pistons are.
or am i completely off in my reasoning and attempt to check leakage with each piston in exactly the same place - tdc?

edit: just realized, i would know where the pistons are even w/o cams and timing belt by taking the spark plugs out, inserting screwdriver, rotating crank, observing screwdriver position - so ignore all the above.

Click to expand...

Thats exactly how you are supposed to perform a leakdown.
You would be halfway done had you started this morning.

and so i am back from my 5-week european vacation, visiting family in the old country. but i'll tell ya, for those not familiar with the situation over there, what a disaster that continent is with the invasion of europe by mid-east muslim rapefugees. disarmed population with no guns in any house to protect their women from rapefugees. but i digress. back to where we were...the saga continues..

so i did the leak down test on the 6 bolt mentioned above. what a disaster. starting w/ cyl#1 - 52%, 47%,28%, 55% respectively. intake valves are fine but all rings and exhaust valves are bad, in addition to the oil leak discussed extensively above.

nevertheless, since everybody in the family is in good mood after i took them to europe so i dont expect anybody complaining about my hording tendencies and cluttering the garage w/ more junk, i couldnt resist and bought this (below) turbo 4g63 from '95 talon for $90.




The oil pump failed on this turbo, bearings were spun, crank is kaput.

Cyl #1 shows 0% on leak down test, Cyl #3 about 35%, cyl #2 nearly 70% and cyl #4 around 80%.

Questions:
1) Is the head from the 4g63T compatible with the 7 bolt block? Can the head be put on?
2) Is it probable, or even possible, to take one of the piston heads from the 4g63T and replace the piston w/ a hole in it in the 7 bolt ? (both engines are stock and I expect the gudgeon pins to be the same size in both the 7 bolt and the turbo.

Just for the sake of it, is it doable? i know the retort might be that if this is non-turbo it's not worth it, but still... there's enough parts here to get at least one motor going, is there not?

1. 95 is a 7 bolt
2. Piston will physically fit but compression ratios and piston to wall clearance are different. It isn't a drop in and go affair. Measurements should be made. I wouldn't even attempt it.
You can use the head but the Intake ports are smaller. Should be used with that intake manifold.
Youd have been better off just buying what you need to fix the nt.

@pauleyman , i know i shouldnt have bought the 4g63T but sometimes things just happen. i was dropping off my merc to get a new wheel bearing and i see the 4g63T on the skid. i asked how much? mechanic said $300. i said i wouldnt give him $50 for that junk. and then 10 min later it was in the back of my suv for $90. anyway i am just like that, collecting junk.

to clarify, when you said "should be used with that manifold..", 'that' meaning the complete 4g63T head with the 4g63T intake manifold should be mated with the '94 7-bolt block (the block with the broken piston in it that is). in other words, dont install the '94 intake manifold on the '95 head. but as far as all oil and coolant passages between the '94 block and '95 head go, it will be a perfect match, i.e. the head gasket for '94 series is the same as the head gasket for the '95 series 4g63T block...? btw, to my great surprise, the '95 4g63T block is a lot different (externally) than the previous gen that i am familiar with.
this should be fun in any case.

If you are planning on dropping that motor into the 1g it cant be done as a bolt in. 2g blocks have no motor mount provisions front or rear
2g have those on the trans.
Its still a good purchase. Just not for a swap.

pauleyman said:

If you are planning on dropping that motor into the 1g it cant be done as a bolt in..

Click to expand...

the thought (drop 2g motor into 1g frame) did not even cross my mind - but not for the reason you mentioned though. i wouldnt do it because the 4g63T requires even more work to rebuild it than the 6-bolt. it's just for parts.
if the 2g head can be mated with the 1g block i will be happy.

i looked on ebay and compared 1g with 2g head gaskets just to get an idea what i am dealing with. the only diff i know of b/w turbo and nonT blocks are the oil squirters and for turbo the head gaskets appear to be the same for 1990-99, like this one here : https://tinyurl.com/j6t7spp (i know, the bore is 0.5 mm larger - but that doesnt change the passages for oil and coolant).
needless to say, just by visual observation, the ebay head gasket is a tiny bit different than the one i am looking at on top of my nt 7bolt 1g block. so, still..based on that visual discrepancy, is it safe, and can i get a confirmation (y/n) before i start gutting, that the 2g head will be a perfect match for the 1g block? passages, bolts, etc. ? thanks

Yes, you can use a 2G head on a 6-bolt block. I believe they have different length head studs and the intake ports are smaller. They should use the same head gasket.

Vegas smith said:

Yes, you can use a 2G head on a 6-bolt block. I believe they have different length head studs and the intake ports are smaller. They should use the same head gasket.

Click to expand...

ok, thanks. so i'll start with getting the head refreshed.

just out of curiosity, what was the rationale in making the intake ports smaller for the 2g? and turbo on top of it? instead of leaving the size of ports the same; if not bigger to begin with? appears to be counterintuitive. at least to me.

Well, the theory is that the 2g head/intake combo has better low/mid range power and the 6-bolt is higher-flowing at higher hp levels. I have not personally confirmed this as I've only ran 6-bolt heads. However, many people are divided on which head is actually "better" and you really won't find a definitive answer out there.

Vegas smith said:

Well, the theory is that the 2g head/intake combo has better low/mid range power and the 6-bolt is higher-flowing at higher hp levels. I have not personally confirmed this as I've only ran 6-bolt heads. However, many people are divided on which head is actually "better" and you really won't find a definitive answer out there.

Click to expand...

ok, thanks. interesting. more so for me as the diff is not fundamental and nothing to be concerned about for my 'going to the store' type of driving.

Many people run the 2g head/6-bolt block combo with great results.

Vegas smith said:

Many people run the 2g head/6-bolt block combo with great results.

Click to expand...

well then, this is going to be a fun trip to the store. just hope the head is not warped when the oil pump failed, the guy lost oil, spun bearings and probably overheated the motor as well. i noticed the balance shaft is missing. mechanic said this engine was raced, he tuned it, it put out 528hp on dyno; but couldnt find the print-out or log so who knows...?

Nobody made 500hp out of that little bitty turbo. If thats a 16g and real you got your moneys worth. Id have goven 90 no problem

pauleyman said:

Nobody made 500hp out of that little bitty turbo. If thats a 16g and real you got your moneys worth. Id have goven 90 no problem

Click to expand...

agreed. i just dont know enough about these things to comment. i just question the whole story. like the oil pump failing story. i see there's balance shaft delete; and no doubt if it is done by amateurs there's potential for blocking or obstructing proper oil flow and starving parts of the engine which would lead to spun bearings; and than blaming the oil pump. i dont know. it was $90 bucks. that motor was probably on its way to the scrap, then i show up and take it off his hands. i needed new head anyway and there's some chance this one could be used.

sacrileger said:

agreed. i just dont know enough about these things to comment. i just question the whole story. like the oil pump failing story. i see there's balance shaft delete; and no doubt if it is done by amateurs there's potential for blocking or obstructing proper oil flow and starving parts of the engine which would lead to spun bearings; and than blaming the oil pump. i dont know. it was $90 bucks. that motor was probably on its way to the scrap, then i show up and take it off his hands. i needed new head anyway and there's some chance this one could be used.

Click to expand...

Be careful acting on a bunch of "deals". You can wind up with a bunch of crap you don't need while you're waiting on funds for quality stuff. I keep buying parts I don't need then I think: man, I guess I'll wait til Christmas to buy some nice injectors".

@pauleyman

pauleyman said:

Nobody made 500hp out of that little bitty turbo. If thats a 16g...

Click to expand...

i took a gander at the turbo that's bolted on and it's this one here, td05h: https://tinyurl.com/z7gc7b4

if that helps anything

Nope. Post pics of that turbo and post all the numbers on the compressor housing

pauleyman said:

Nope. Post pics of that turbo and post all the numbers on the compressor housing

Click to expand...

as requested:

EVO 16G

http://www.dsmtuners.com/threads/td05h-turbo-part-numbers-14b-16g.313105/

Vegas smith said:

EVO 16G

Click to expand...

i see what you did there. looks like it's the Evo III Big 16G 49178-01470
teh complete set:
S0410013025
49178-01470

so i guess too small for the 528hp narrative, eh?

Looks like you got a great deal. Yeah, no way they're hitting that number unless their name is Curt Brown.

i'd like to come back to this idea:

pauleyman said:

1. 95 is a 7 bolt
2. Piston will physically fit but compression ratios and piston to wall clearance are different. It isn't a drop in and go affair. Measurements should be made. I wouldn't even attempt it.

Click to expand...

so i finally got around to pulling the damaged piston out. here are pics.





the bearings are absolutely immaculate. anyway, i did some reading on fitting the '95 7bolt turbo piston into the '94 7bolt n/t. it appears that it is very doable. i wonder if i could get a definite confirmation that
a) the bore of '94 7bolt n/t = '95T 7bolt = 85mm
b) the piston wrist pin in '94 7bolt n/t = '95T 7bolt = 22mm; therefore,
c) the '95T 7bolt piston will fit onto the '94 7bolt n/t rods.
d) overall stock piston size: '94 7bolt n/t = '95T 7bolt; therefore,
e) the '95T 7bolt piston with 2g rings installed on the '94 7bolt n/t rods will fit into the '94 7bolt n/t bore - and work without any machining whatsoever.

for the above facts, i rely on information contained in these threads:
https://tinyurl.com/zvu3yrd
https://tinyurl.com/gn3ejmq
https://tinyurl.com/h8x2kby
https://tinyurl.com/gw59ryy

needless to say, these threads are over 10yrs old and i wonder, after a decade, if i have been misinformed by claims in the above threads?
your opinion would be appreciated.

Thats kinda accurate. First things first. First off there are no turbo vs nt rods. Its 6 bolt or 7bolt. Any 7 bolt piston will physically Install on a 7 bolt rod. Likewise for 6 bolt. Now then.....it isnt just bore youre concerned with. Its piston to wall clearance. Turbo and nt are different. You may not need machining but you most certainly should measure bores. Taper, out of round all come into play in any assembly and the final hone to achieve proper piston to wall clearance.

pauleyman said:

Thats kinda accurate. First things first. First off there are no turbo vs nt rods. Its 6 bolt or 7bolt. Any 7 bolt piston will physically Install on a 7 bolt rod. Likewise for 6 bolt. Now then.....it isnt just bore youre concerned with. Its piston to wall clearance. Turbo and nt are different. You may not need machining but you most certainly should measure bores. Taper, out of round all come into play in any assembly and the final hone to achieve proper piston to wall clearance.

Click to expand...

pauleyman, thank you for your brisk reply. this is very, very encouraging. the info in listed links is clear; however, it's good to get confirmation before taking apart another engine.
now, regarding the piston to wall clearance resulting in different compression ratios(??), and i am just making sure, this should not matter much in my case since this engine is not going to see the redline with me driving to the store to get a carton of milk and bag of diapers (depends for me) j.k.; the chance that the '95 piston will rub against the cylinder wall is virtually nil, i gather? i'll post pics of the '95 piston once i fish it out.