bliffle

I'm trying to find the thread about how to remove and replace the manifold orings. Found some interesting things with search, but not the complete thread. I know it's there someplace. I'm replacing the intake orings on my 85GSL 12A, with CA smog.

Anybody got the thread pointer?

Sgt.Stinkfist

iTrader: (6)

so... youre just replacing the coolant o-rings between the manifold and block? sounds pretty stait forward to me. remove manifold, replace intake gasket and o-rings, install manifold. it does help to have a FSM or another manual for the whole dissasembly / reassembly process though.

nick812

Theres a tread talking about installing freeze plugs. Search freeze plug.

slashdawg00110

nick beat me to the punch. Here's the link:

https://www.rx7club.com/1st-generation-specific-1979-1985-18/how-install-freeze-plugs-531971/

bliffle

OK, got it all off, put a little permatex on the orings to hold them in place, replaced manifold. But I hafta replace those teeny tiny clear tubes because they are utterly fragile. Any idea where to go, what to ask for?

I'm heading out now to try to scare up some 1mm tubing at Kohlweiss or Industrial Hardware.

slashdawg00110

tiny clear tubes? The lines that run from the OMP to the carb?

bliffle

Yes. The tiny clear tubes that emerge from the black hose elbows. As in the picture on page 2-8 of the 85 Manual at:

http://www.wankel.net/~krwright/files/manuals/1985_RX7_FSM/85RX7(2)lubrication.pdf

I'm guessing that the elbow/tube combo can be replaced by just a simple tube of the correct ID.

bliffle

I installed some of that special red vacuum tubing from mazdatrix I think it's silicon-based) in place of the broken small diameter tubing that ran from the OMP to the carb. Haven't tried starting yet since my mechanic was called away for family problems. I don't know whether that tubing is OK or I should try to get something like the original stuff since it passes oil instead of air.

Rogue_Wulff

Anything can work for a while. Oil will soften most any rubber-based product, including the stock "Elbows" on each end. I don't know if silicon-based hose is oil resistant or not, but it will work for a while. Without the little clamps Mazda used on those rubber elbows, they would have started swelling and leaking after a year or 2.
Mazdatrix sells the hard plastic lines, about $10-15 each.

bliffle

Bingo! Thanks Rogue, I didn't know M'trix had special lines, so I looked it up and just ordered them. I LIKE having OEM parts wherever possible.

Rogue_Wulff

NP. The OEM lines may not look fancy, but they work quite well. I'm thinking of ordering a new set, for when the time comes to replace mine. MT has a good price on those little buggers to boot.

bliffle

Yup, only $18 apiece (2 required). They're preformed and precut to fit just right.

bliffle

I'm trying to invent a kit that I can use to provide manifold injection lube from a tank of premix, when available, then switch to sump oil when no premix is available. I have a few designs roughed out:

1-float in the premix tank operates electrical valve to switch between sump oil and premix. Too bad it depends on electricity and 3-way valve is before the OMP, thus necessitating OMP mechaical mount changes.

2-Hydraulic computer system that has OMP always pumping sump oil into a hydraulic gate that either operates a motor-pump set to supply premix (then returns oil to sump), or bypasses the (off) premix to go directly to carb/manifold. Gate is operated by hydraulic head in premix tank.

3-combination of 1 & 2 where gate is operated electrically by premix tank float.

4-always supply carb from tank (with an added OMP) and allow sump oil into tank when level is too low.