mazda 6

[maker1to2]

just picked up a non running 2003 6i (2.3) with 154k off a trade

came across a few problems thought I discuss!

was told it needs a fuel pump forgot the code, wasnt told it had a misfire yet ignition parts were replaced and compression looks like

dry compression tested

cylinder 4 (180) cylinder 3 (155) cylinder 2 (150) cylinder 1 (125)

think I heard some ringage when cranking

most-likely stuck rings

questions go easy way or hard way: after performing a leak down test

i. easy

has anyone tried mystery/seafoam mix poured in to chamber to soak? (as I discuss I'm trying this method will be 48hrs tomorrow afternoon)

or

some other mixture (acetone/atf)

etc

ii. hard way

(engine swap) finding low mileage or decent salvage engines are next to none most high mileage cars are abused; cost of living here is expensive.

so a mini rebuild...ie whatever is broke fixing it

how likely is it that I could just replace rings and hone cylinders maybe grey gasket sealer for oil pan/valve cover then spend no more!

or are:

1. most vehicles head bolts stretch 1 time use

2. head gaskets a 1 time use

[humanshield]

Marvel mystery oil does work. You could try it. No harm in trying. But it can't fix bad head gaskets or broken rings etc.

With a salvage engine swap it's sometimes hard to determine the condition without pulling the oil pan to check the bearings and doing a leakdown compression test. A LOT of work if it turns out bad as well.

I would say more than likely the engine was overheated at some point. One of the most common causes of engine failure. But then the Chrysler vehicle I bought a few years ago, I don't think the owners knew it had oil that needed to be changed and was run out of sludge (I doubt the oil was ever changed). ALL bearings had to be replaced....and even with it knocking and banging like a drum full of rocks, they kept trying to drive it ! $1200 later it has a fully rebuilt engine.

You might get away with rings and a cylinder hone....but to do it right, you'd probably need to have the head rebuilt professionally and straightened. It's hard to say until you get in there and see exactly what the issue is. You could get lucky and it only needs a head gasket.

If the rest of the car is in really good shape a full rebuild might be worth it. If not, it's hard to say how far you'll need to go to get it running properly if the MMO doesn't work.