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Discussion Starter · #1 ·
Hi guys

Just changed the head gasket on an AT TX5 Turbo Auto, had the head reco'd, head gasket kit, etc.

Comp. tested it before replacing the head gasket... all on about 75'ish.

Ran like a bag of s**t when I fired it up... someone came and told me "You're timings out, sounds retarded"
"No it's not (You sound retarded!!). Timing marks are lined up, couldn't adjust ignition timing cos the thing wouldn't idle (although as soon as he came he fired it up and it idled)"

Anyway, reason it ran like crap was that the injector terminals were screwed... replaced them... fired it up... still sounds not quite right... prior to that, I did a comp. test... all around 125 except for cyl. 1 which was at 75, poured a bit of oil down that cylinder, did the test again... 115! So I personally think the rings aren't sealing up properly.
If I rev it, it sounds fine (which made me think it was a vac. leak, possibly the guy who did the head didn't get the sealing of the valves right, etc.)
If I pull number one injector plug off, runs practically the same on idle. If I rev it with the plug off, runs on 3 cylinders (of course).

Any suggestions?
 

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if one of the hla's is not bled properly then the valve will stick open a little and it will also make a tapping noise ( a noisy lifter) Check the plugs are still good and all the leads are correct i had a similar problem on my mx6 a couple of months ago. The compression may be out to if the head gasket hasnt sealed properly either so i would recommend undoing all the head studs to finger tight and retorque them in the corect order to the correct torque.

Youhave done all those havent you?
 

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Discussion Starter · #3 ·
Thanks for the suggestions.

Usually a noisy lifter will be due to the lifter going too soft... and that'd cause the valve to stay closed. If it's gone solid, it probably won't be noisy... It goes alright when you drive it... just when it returns to idle or low revs... it starts to act up.

I personally don't like undoing head bolts once they've been given the final tension... especially if it's been running for a while. They're all at approx 86nM. Won't be touching the car today... it's a bit cold today at 40 something degrees! :/
 

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i got told the lifters will be noisy if they dont bleed properly and eave the valveopen a little to much, i have on on my car i think that i have to take out and squash in a vice so it works propery.

And i also got told that you need to undo the head bolts to retention them after a while of driving, but you do it one at a time and only undo them so there is no strain on them i.e you can turn them with your finger, then retighten to make sure the head is all pulled down properly.

And what do you mean a bit cold, it was a little hot but not that bad.
 

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Abdul, I still think it'll be either a ring land or a damaged compression ring. Maybe it broke one???
 

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for the compression test it NEEDS to be between 119 and 171 psi after 4 turns of the crank. no higher or lower and there cant be a difference of more than 10%. so if cylinder 1 is at 150 psi (10% of 150=15) then cylenders 2-4/6 cant be any higher than 165 or lower than 135 if yours read at only 115 then you have a leak somewhere in your cylinder probably your compression seal or the test wasnt done correctly.
 

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Discussion Starter · #12 ·
lol.... holy thread resurrection batman!

The car is still running til today suprisingly on the same head/motor assembly. The rough idle is a little better. The only thing I've done to it since then is that I reco'd the brake master cylinder for him. Car still goes good, and from what I've heard and what I know of him, he doesn't exactly cruise the car 24/7.
 
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