Well today I went down to autozone and spent $50 dollars on a compression tester and had my hopes up that my engine would be 95 psi or better and well I got it hooked up to the front rotor housing and it sucked it reads at 70 psi but the good thing is that it is 3 even snaps of 70 and hoping that the rear rotor was better I hooked it up to that on and well it was the same but my quetion is how low can the compression be before you have to start using ATF if you want to start it.

Thanks

 

You should just go ahead and do the full atf trick...if your car is not experienceing any problems being that you say you were expecting 95 then go ahead and do the trick and see if that helps compression...how long did you hold out the starter you should do it for atleast 15 seconds... -Gabe

 

Why would you want to put transmission fluid in it exactly?

 

Just curious. If you have the engine warm, full open throttle, the relief valve installed in the compression tester, what do you capture on the gauge after spinning the engine for three or four seconds??????? Is it the same as the bounces you saw? 70psi? Just curious. Make sure the throttle is wide open, fuel injectors disabled.

You did remember to open the throttle fully prior to checking the bounces in the test you did???

 

The ATF in the engine will seal everything a little better and if the engine has horrible compression and won't start on it's own the ATF will raise the compression enough most of the time to start it and for the other reply no I didn't open the trottle at all I didn't think about that maybe that is why it is reading so low


Thanks

 

I don't remember what the factory specs were in psi, I use a rotory compression tester and it reads in kg. The main thing is the consistency between each apex seal and a low variance between the front and rear rotor. IF you didn't open the throttle all the way, your reading will be way off. You can't have complete compression if it's starving for air. Also, make sure you have either removed the schrader valve on the tester or at least hold it down while spinning the engine.
dave

 

there are 2 tests. you did the first one which was to check for all 3 even. I only get 60-70 for that too. but it really depends on the gauge...

now do it again with the pin in and and let it build up a few turns and take a reading.

and make sure the engine is warm and throttle open

 

50 bux sheeze I got mine from advanced for 19.99

 

ATF is a corrosive chemical (not to mention not made to be put in an engine). Use normal motor oil or 2 stroke oil if you want to do something like that.

 

Well a new update on the whole subject I looked at the oil and noticed that it is as this as water and just a little thicker when cold still thinner than when I bougth it it is 10w-30 and I think it might be the problem but when I first put it in the oil and the oil pressure were fine but I got to smelling the oil in the engine and it smells very strong of gas not anything like oil and I just changed it not evern a week ago also what puzzles me is that I just had full service cleanings done to all of the fuel injectors so they aren't leaking anyone know why my oil smells like gas

 

sounds like you got collent leaking into you oil, do it smell sweet, or is it a eye watering gas smell?

 

It doesn't smell sweat at all it smells just like gas I think I will just change the oil one more time because I had the wrong king of injectors in the intake so I think that might have been the problem well see I hope that is what it is

 

I got a better deal than that. When I bought the car the guy left it in the engine bay,

 

The ATF or Oil does give you a better seal. Thats called a wet compression. However the ATF has cleaning clemicals in it that will rid your motor of carbon deposits and lossen stiffness in seals to create a better compression. However, it creates ALOT of smoke until it's gone/burned off. I'm sure if a search on ATF is done there's a complete explaination.

 

.... Drive the car harder, that will get rid of the carbon too. ATF also fouls plugs, o2 sensors, cats etc.

 

ASE Master Cert. Tech and books tell me that atf will not hurt a 02 sesnor one bit...shouldnt clog the cat either..plugs...obviously.

I agree with Devil about what he said too

going out and "driving the car harder" isnt always your best bet...I Lost 2 apex seals follwing advice like that. Getting MMO or ATF in there to eat away at the carbon and keep apex seals from locking is what i should have done...ive seen what atf will do to carbon and mmo as well...you can see the carbon just drip off your rotors.

 

Could you tell me what MMO is and were I can get some and I do drive the car pretty hard about half the time which isn't but maybe five minutes I try not to because I know it shortens the engine life but it is to much fun to miss out on. Also I want something, if I do put a chemical in the engine to break the carbon up completly so it won't wedge it's self in between the apex seal and the rotor housing will MMO do that has anyone tried.


Thanks

 

the burnt atf will make a residue over the o2 sensor which also plugs the cat or some ****. I dont like atf, I would never recommend someone use it. Im not looking that far into it.

 

also if u want higher comp u can remove the washers from ur plugs or get thinner ones. it will bring spark closer which is a plus in 4 stroke engines. pls search up more on that tho

 

The best thing you can do is run some water through it. No, you cant hydrolock a rotary. No, water wont hurt anything internal or external, in fact it cleans out crap very well. This is a virtual steam cleaning process for the engine internals. Have the engine running, have a gallon jug of water, a vacuum hose. Grab the throttle and open it up some to say 4-5krpm, hold it there, dip the vacuum hose into the water and let it suck...dont let the car die. You want a hose that feeds both front and rear chambers, depending on models and years this is in different places. I do this treatment weekly to one engine or another around here; at worst it doesnt make any difference, at best, it makes a WORLD of difference.

IT has been real cold here lately, and this one local guy has a car that has low compression and keeps flooding (he doesnt drive it regularly). Even when I get it started, it runs extremely rough and wont consider idling below 1500. After running 1 gallon of water through it, it settles down adn runs perfectly, 750 idle, until the next week when he tries to start it and discovers his battery is too weak to bump it quick enough to overcome low compression.

 

Well for drOx I'm not woried about the cats they are gutted and for the O2 sensor I don't know I haven't ran any ATF threw it in a long time anyway. And for hypntyz7 could you explain were a line like that is or posibly take a picture also I'll try surching


Thanks

 

Boost sensor or bov. You wont be making much boost at like 4k on a free rev anyways.

 

As I said it depends on year and model, and as of yet I havent seen mention of that information...

neither of these feed both front and rear rotors/intake runners. we dont even know that he has a turbo model, afaik...

 

No it is an 1988 NA with cruise control that adds a couple more lines sorry about not telling you that I unhooked the cruise control line because it had a strong suction or at least better and stronger than the rest that I found and let it drink about a court or so and it ran so bad that I couldn't stand it any more and quit and also what sucks now is that it smokes a little again when I start it up OH the good memories that came back unfortinatly. The cruise control line only feeds the back rotor I think would it cause rust if I put the water threw one of the lines on the dynamic chamber by that I mean rust on any of the butter fly lines on the inside

Thanks

 

use the top fat line on front of the dynamic chamber. Atatch another line to it, (the hose, not the manifold) and let it drink through there...this distrubutes water evenly between front and rear. Let it drink a gallon or 2, and repeat this every 2-3 months. I'd recommend this for anyone.