bliffle

We just put a new manifold gasket and ORings into the 85GSL and now it starts but runs only on #1. Looks like fuel feed is OK since both Accelerator pumps spray fuel. So maybe it isn't floats. Figured it was #2 not running by disconnecting spark from each rotor in turn.

I figure we screwed up a smog hose. And when I peer into the jungle-o-hoses I see a shiny nipple! Huh? But all the hoses seem occupied.

Here's some snaps. You can see the carb at the right.

74RX4

iTrader: (10)

On my 85 GSL that nipple has a 2" hose with a T. Hose on one side of the T goes to small nipple on bottom of air cleaner. Hose on the other side goes to the bottom of the black cylindrical thing in the upper center of your pictures.

Rx-7Doctor

iTrader: (13)

The only thing I can think of that would prevent fire(Fuel actually) to the rear housing is the shutter valve being activated at all times or the linkage is flopped over preventing fuel from going in.

bliffle

My 'apprentice mechanic' is working on this, and I'm just supervising and debugging. We got the engine running better when we re-analyzed the hose routings and covered that shiny nipple. Now, both rotors fire, but it doesn't idle. Curiously, the choke doesn't stay out.

I'm going to just sanitize the hosing by replacing all the vacuum hoses with the nice new ones I got from mazdatrix, under the premise that we have a sneaky vacuum leak somewhere, since that seems most likely. I figure we cracked a hose jostling the carb around while changing the manifold gasket. The existing hoses seem limber and sound, but they are hardened onto the nipples, so I'll have him cut them away carefully, one at a time, so as not to break a brittle plastic nipple.

How does that linkage get flopped over?

Rx-7Doctor

iTrader: (13)

Concerning the choke problem. Did you unplug the thermo sensor at the back of the water pump housing or possibly break the wires by accident?
On the idle issue. Are all the vacuum hoses routed correctly and the wiring all hooked up?

bliffle

I told the AM to change all the vac hoses, one at a time, but he reports that it's impossible without removing the carb, which surprises me: I thought I saw a bunch of easily removed hoses. But he re-checked everything for the tenth time and then had to quit because a horse stepped on his hand a couple days ago and it's swelling and hurting.

But I had him check the timing first and he reports that it's out-of-time: the pulley notch is about 3/8" towards the passenger side from the timing peg. I forget if that's advance or retard, but how could he have jostled the timing without touching the distributor?

Oh well, I'll mark the timing notch(es) with white paint so they showup clearly and reset the timing myself. Absence of the white paint tells me I've never timed this car myself in the 4 years I've owned it. I'd still like to find out how to static-time this electronic system like we used to do with the old points systems. Simpler, faster, and saves a lot of screwing around.

bliffle

The AM went thru all the hoses and wires, etc., rectified everything, and it runs fine now. Didn't replace the hoses because they are so burned onto the nipples it might be risky removing them. We'll postpone that little job.

But there's a puddle of oil under the car and the lower engine and pan etc., is covered with oil. It leaves a trail of oil when driven. That's totally new. It never leaked oil before. We'll drop the pan and at least install a new pan gasket tomorrow.

But what caused the oil leak? We only ran the engine for a minute or so each time we tested it. Usually less. The only thing I can figure is that somehow a misconnected smog tube caused an unusual pressure condition that either forced oil out somewhere or blew some oil gasket. I worry that replacing the pan gasket isn't the right thing and won't solve the problem.

bliffle

It's not the pan, it's the good old beehive leaking. Discovered when car was put up on jackstands. The AM did the beehive on the 83 a couple weeks ago, so this is pretty easy.

I'd like to find a better ORing, maybe made of some modern material better than the neoprene that these are usually made of, and stock up on them.

I've decided NOT to convert to the air/oil cooler under the radiator because it's a lot of work and I think an oil/water cooler should cool better than an oil/air cooler.

bliffle

Apparently, the 85 beehive is a heck of a lot harder than the 83 because there's a lot more hardware and wiring in the way. Looks like an all day job.

t_g_farrell

iTrader: (1)

Sounds like your having too much fun.

I think the oil to water cooler is less effective than the oil to air using an FMOC because the beehive gets water thats pretty much already heated up. Notice they have never used it on a 13B from 84 on thru 2 and 3rd gens. My pet theory is the beehive was a Mazda bean counters wet dream to reduce some of the costs on the 7.

bliffle

IMO the purpose is to stabilize the oil temp, not just make it colder occasionally. If you can count on knowing what the temp will be then you can design a lube to deal with it. But if the operating temp varies widely you have a more severe problem. Liquid to liquid heat transfer is much much better than liquid to air, which is why my 69 VW bus engine blewup every other year by pulling the steel head studs out of the alloy case due to differential expansion rates.

Do they still use those aircooled engines in VW buses?