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-   -   intake pressure tester (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/intake-pressure-tester-997824/)

alritzer 05-10-12 07:18 AM


Originally Posted by sharingan 19 (Post 11085288)
The system doesn't stay pressurized for very long even when there are no leaks, so you have to work quick.

I hooked it directly to the turbo and pressurized the intake using line from a compressor. It really works best when you have someone else to pressurize the system while you look/listen for leaks.

OK, that is exactly how I am doing it. But, I can hear the air continue to flow, it never starts to pressurize.

misterstyx69 05-10-12 10:09 AM

On a S5 TII lower manifold the injector bleeds are ganged together with a small 5 inch hose..then it carries over to another vacuum nipple that faces the firewall.
Another vacuum nipple is pretty well in the center of the Inside lower manifold,between the injector locations.
..and there is another one that operates the Oil injectors.sticks straight up in between the oil injector locations.If your oil injectors are removed did you Cap off the oil injector locations with bolts and cap the oil injector vacuum nipple????
..Maybe check out those vacuum nipples as a source of leakage.If not capped you will hear Air..Rushing out,like crazy, when you put the compressor to the intake.

alritzer 05-10-12 10:09 AM

I used a leak down tester on her and it shows 100% leak down. As far as I can tell, there are not any air leaks until after the air passes through the LIM and into the short block.
So, after wasting another couple of days....... its time to find a smoke machine.

Black Knight RX7 FC3S 05-10-12 10:22 AM

You can try just pressurizing the engine itself without going through the intercooler piping. connect the pressure coupling to the throttle body elbow and try it again.
If you got the boost gauge hooked up to the manifold. Up the air pressure of the air source you are using and see if the boost gauge moves. Just try and stay below 15psi

alritzer 05-10-12 03:29 PM


Originally Posted by Black Knight RX7 FC3S (Post 11085979)
You can try just pressurizing the engine itself without going through the intercooler piping. connect the pressure coupling to the throttle body elbow and try it again.

Thanks, I tried pressurizing from the elbow like you mentioned and I could hear the leak better. So, I called a couple of friends, pulled the UIM again and this time we found several big leaks plus a small one. it was leaking at the throttle body elbow where it mates the throttle body, a primary injector had a crushed seal and was leaking and a vacuum nipple on the LIM was uncapped. The vacuum nipple was buried under a bunch of vacuum hoses and was difficult to see.

thanks
ash

alritzer 05-10-12 03:33 PM


Originally Posted by misterstyx69 (Post 11085200)
put the lit end of a cuban cigar into the mouth of a 2litre bottle and squeeze..Instant smoke machine.

Thanks for the tip. I tried to find a smoke machine but nobody had one so I used your idea and I shot 10 psi of air in the other end. Worked pretty good but sure went through cigars fast. Only took 2 cigars until I knew for sure that there was a leak under the UIM.

thanks

alritzer 05-10-12 03:36 PM

Hopefully the leaks were enough to cause the problem. We won't be able to put her back together until Friday evening or Saturday.

I'll let you guys know.

thanks to everybody.......... :) :)

:)

:nod:

SpikeDerailed 05-10-12 06:42 PM


Originally Posted by alritzer (Post 11086312)
Thanks, I tried pressurizing from the elbow like you mentioned and I could hear the leak better. So, I called a couple of friends, pulled the UIM again and this time we found several big leaks plus a small one. it was leaking at the throttle body elbow where it mates the throttle body, a primary injector had a crushed seal and was leaking and a vacuum nipple on the LIM was uncapped. The vacuum nipple was buried under a bunch of vacuum hoses and was difficult to see.

thanks
ash

That wouldnt be the one in the dead center of the lim right at the primary ports would it? If so, that the line for the primary air bleed sockets. That should be hooked up to metered air at the vac ports next the the TB on the UIM.

alritzer 05-10-12 07:37 PM


Originally Posted by SpikeDerailed (Post 11086472)
That wouldnt be the one in the dead center of the lim right at the primary ports would it? If so, that the line for the primary air bleed sockets. That should be hooked up to metered air at the vac ports next the the TB on the UIM.

Yes, that is the one. The vac ports that are closest to the primary injectors are just connected to each other. Somebody just took a piece of tubing and ran it from one injector to the other.
There is a vac port on the bottom of the lim that goes to the sec fuel rail. Another port (uim , firewall side, mid port) goes to the oil injector gang.
I'm not sure where you are saying the one that was open should go. This setup came like this, nothing the po did made sense.
As far as the uim, only 1 of 3 of the ports on the firewall side are used and all 3 on the forward side are capped.
There is another vac port on the outer side of the lim that goes to the wastegate valve.

misterstyx69 05-10-12 08:06 PM


Originally Posted by misterstyx69 (Post 11085200)
put the lit end of a cuban cigar into the mouth of a 2litre bottle and squeeze..Instant smoke machine.

Holy shit!..IT worked???
My Brain storm idea worked?..YAY!
My original idea was to make it like the vacuum tester and put a valve at the bottom of the bottle so you could put the compressor to it,But I didn't think I could explain it correctly..so I opted for just tossing it at the mouth of the bottle and Squeeze!!!!

jackhild59 05-10-12 08:23 PM


Originally Posted by misterstyx69 (Post 11085200)
put the lit end of a cuban cigar into the mouth of a 2litre bottle and squeeze..Instant smoke machine.

You *could* have suggested this with a White Owl, or a Swisher Sweet.

Cuban indeed...:icon_no2:

misterstyx69 05-10-12 09:36 PM


Originally Posted by jackhild59 (Post 11086562)
You *could* have suggested this with a White Owl, or a Swisher Sweet.

Cuban indeed...:icon_no2:

Insert FIDEL and light his head!..how's that?..
I don't smoke cigars and the only way I could think of to Explain a BIG cigar was to use the Term "cuban cigar".
I don't think Dog Rocket would have went over as a good description!

alritzer 05-12-12 12:03 PM


Originally Posted by misterstyx69 (Post 11086547)
Holy shit!..IT worked???
My Brain storm idea worked?..YAY!
My original idea was to make it like the vacuum tester and put a valve at the bottom of the bottle so you could put the compressor to it,But I didn't think I could explain it correctly..so I opted for just tossing it at the mouth of the bottle and Squeeze!!!!

Well, the just 'squeeze' part didn't work but the overall idea work fine. Boy do those cigars stink. Eight hours later the garage still smelled like cigar.

But, yea, good idea.
ash

alritzer 05-12-12 12:07 PM


Originally Posted by misterstyx69 (Post 11086644)
Insert FIDEL and light his head!..how's that?..
I don't smoke cigars and the only way I could think of to Explain a BIG cigar was to use the Term "cuban cigar".
I don't think Dog Rocket would have went over as a good description!

No problem, I just asked the lady at the store for "a big fat, cheap cigar" and then of course she wanted to see my license............ its like I look older than 18.

jackhild59 05-12-12 12:30 PM


Originally Posted by misterstyx69 (Post 11086644)
Insert FIDEL and light his head!..how's that?..
I don't smoke cigars and the only way I could think of to Explain a BIG cigar was to use the Term "cuban cigar".
I don't think Dog Rocket would have went over as a good description!

You misunderstand. We cannot buy Cuban made cigars in USA. We are forced legally to smoke Dominican, Nicaraguan, Honduran etc.

arghx 05-12-12 02:31 PM

Ok here's the thing.

I've done many pressure tests on Rx-7's and other cars.

Do not worry about "overpressurising" the engine with the tester. You should have the the tester (PVC cap) connected to the compressor inlet or TB elbow. Use a coupler and two screw clamps (normal worm gear clamps). The tester will pop out (it will be loud and startling) before you overpressurize anything.

Slowly turn the regulator up until the actual boost gauge says 5psi, or all the way up to 10-12psi... it might take 50psi on the air compressor regulator itself. If the leaks are really bad, you won't even build pressure on your boost gauge. Use the soapy water trick to pin down leaks. There are other methods: you can actually build an LIM tester with separate ports for each runner. You can do it with the engine out of the vehicle by pressurizing the TB elbow and blocking off any open hoses.

misterstyx69 05-12-12 06:54 PM


Originally Posted by jackhild59 (Post 11088270)
You misunderstand. We cannot buy Cuban made cigars in USA. We are forced legally to smoke Dominican, Nicaraguan, Honduran etc.

Oh,I get it now.
they subcontract out ......like Nike....lol!
( I forgot about that..Cuban cigars being a No-NO!)


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