Mazda 1992 GTX turbo Awd (new mrfxit project)

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mrfxit, Feb 18, 8:34pm
Facts 1st .
Mazda 1992 GTX turbo Awd 1800cc 5 manual
Tappets are pretty dang noisy on 1st startup & every startup even when "true" hot
From cold it can take up to 30 min or more to settle down
From hot upwards of 5 min or more.
Once running & tappets settled it's ok.
Seems to be a slight engine miss while rattling
It's had an engine flush & new oil/filter thats improved the time delay a bit better up to where it is now
Runs like an intact male cat with the vet after it ;-( . ;-)

Questions .
What is it most likely to be & what other options could it be
How to cure it with the least expense & other reasonable options
What tappet adjustment system do they use
Probable costs involved in the above questions please.

therafter1, Feb 18, 8:39pm
Hydraulic, not a lot of options other than expensive hydraulic lifter replacement.

Hit it with a dose of ProMa MBL8 and see if that shuts it up.

Avoid engine flush like the plague !

mrfxit, Feb 18, 8:41pm
Next oil change will probably be a sump off/ clean job

unbeatabull, Feb 18, 8:43pm
Id chuck some Pro Ma and maybe try some thicker oil too. As above suggested, most likely sounds like a Hydraulic lifter.

therafter1, Feb 18, 8:46pm
Yep, give the oil pickup strainer a good eyeballing and if necessary pull it out and clean it up. It is not at all unusual for engine flush to convert varnish back into gooey liquid varnish which then accumulates on the pick up and successfully blocks it.

At the end of the day, others may have tried to shut it up with the use of engine flush which has then exacerbated a minor existing problem that could have been solved with the addition of ProMa at each service.

Usually good strong little engines, but being turbo I would rigorously adhere to 10k service intervals and always use the correct grade of good quality oil.

mrfxit, Feb 18, 8:47pm
Yep & it's got 225K on it but still strong & no smoke or other rattles
Apparently the last flush about 300km's ago was the 'flush in a bottle stuff"/ oil changed & driven back from Napier to Hamilton

So sump off & clean
My mix of 50/50 car oil /diesel fuel for a flush, then new oil/ filter & a dose of Proma MBL8

mrfxit, Feb 18, 8:52pm
Apart from the classic lifter blockage, do the cams/ bearings/ lobes / cam oil galleys etc give any hassles (normally)

thegravelracer, Feb 18, 9:07pm
lol, what "tappets"

therafter1, Feb 18, 9:13pm
The ones wot are tapping lol.

Once again, the times they are a changing, and anything including bucket and shim that actuates valves seems to be referred to as a tappet lol

mrfxit, Feb 18, 9:41pm
LOL yea wot eva

Still relevant,
Dang things are tapping pretty hard
Some have shim pads
Some have shim buckets
Some are Hydraulic
All have a set of clearances or tensions to set

therafter1, Feb 18, 9:49pm
I wasn??

therafter1, Feb 18, 9:52pm
I don??

mrfxit, Feb 18, 10:13pm
Yep most likely hydraulic.
Yep understood the light hearted jab, thats why the "LOL yea wot eva" txt speak.

Time & a bit of digging will tellas to how far the repairs go.
********
Well not "tappets" as in adjustable double arm on shaft type.
Variations of the same, used to be screw adjustable, then a mix of shims/ buckets& hydraulic & now mostly hydraulic.
Same job, different ways.
They all still "tap" when loose

familiadude, Feb 18, 10:23pm
Mine does the same thing if I let it sit for a month or two it will startup and sound like an old mitsi. I normally take it for a drive then once up to temp give it a good boost in second and third normally gets rid of it

mrfxit, Feb 18, 11:43pm
LOL . oh dear, still not a healthy thing to do tho

doug207, Feb 19, 3:54am
As said throw proma in it. But that's only a bandage.

A second head will set you back bugger all, chances are the galleries are all full of burnt, crap oil.
Might be worth doing a pressure check on it.
They're laughable cars anyway :P

snoopy221, Feb 19, 4:07am
pro-ma.MBL8

End of story.
Essentially it's moly slip graphite and the small lifters have a very small hole that getzz zee ole *oil varnish*
no sealie leakky dooown RATTLE

Cleaning won't achieve what proma WILL.
iT ALLOWS A SEAL

mrfxit, Feb 19, 4:23am
I wasn't laughing when my nephew took me for a blast in his 1 a few years ago.
Mad as a hatter & just as twisted.

mrfxit, Feb 19, 4:36am
Yep looks like it's going to get that after a sump clean & my flush.
Might as well get what crud out that we can 1st.

kdcentralni, Feb 19, 5:52am
Rear car now!

fordcrzy, Feb 22, 5:53am
the lifters can simply be removed/cleaned and re-oiled.they seem to trap crap oil. if you do a search on "miata lifter clean" or something similar youll see how to do it. if your doing a cambelt change then its a simple add on process. hell i think you can pick up a whole set of new lifters on ebay for about 65 US dollars

fordcrzy, Feb 22, 7:04am

xs1100, Feb 22, 8:08am
look up jr cozy featured in fast fours and rotaries now thats one fast gtx

xs1100, Feb 23, 1:14am
hes also spent a fortune on it to date so not really stock standard now

carkitter, Feb 24, 12:15am
lol!
I think you meant rare. but you could be right.

I think you should do a full rebuild on the engine. It's an unknown quantity and with 225,000kms on it and sticky hydraulic lifters as a sign of delayed maintenance, I'd recommend a rebuild before something breaks. Anything less is just delaying the inevitable. Those engines are known for shattering pistons and burning / bending valves when cheaply modified and abused by previous owners. Better to do the rebuild with a head intact, and without scored cylinder bores and a sump full of debris.

I like those cars, it'd be a great project.