Cascade Crew

[scott in wa.]

Well, we got the new gears in and the rear end installed,
Now we are waiting on the little round clip that holds the e-brake cable in place on the backing plates. May have to go to the wrecking yard for these.

We started to try and run down why the fans are not coming on.
This is a 91 harness s/d into an 88 tbi car.
I have been reading the duel fan woes post as well.

The relays, fuel pump, and two fan relays look to be the same. They are the rounded typ not the square typ like the 87
I switched all the relays around, the fuel pump works with all of them so Iam thinking its not the relays, also they do not come on when grounded. hummm.
Does the 91 s/d fans work the same as the rest of the years as far as duel fans go.??

Almost ready to drive, it’s been another long project.



Anyway, your input is needed.

Thanks
Scott

[scott in wa.]

I think it may be a power feed problem.

I pulled the relays and do have 12 volts at one of the plugs
I think its a black wire with purple stripe on one and the other is a black with red stripe. they do have power when ignition is on.

Scott

[Twilightoptics]

Scott:

On my car the Fan relays are by the battery and the radiator. 1 relay for each fan. just follow the fan wires.

Let's talk about Fan #1. The one the computer controls.

There will be 4 wires on the relay. 2 fat and 2 small. The 2 fat wires are to power the fan. Battery power to the relay and then to the fan and it grounds or something like that.

The 2 small wires: 1 is ignition power (key on) one is a ground. The grounded wire is normally open (that is to say it's normally not grounded). The ECM will ground that wire, which enables the relay to click on, and fan on.



Fan #2 is identical with the exception of the small ground wire. The small ground wire is grounded to the block to turn the relay on, through the temp switch.

[scott in wa.]

Thanks
Humm,
My relays are on the firewall driver’s side. This is the 91 s/d harness with the round or oval looking relays, along with the fuel pump relay.
I thought you also had the same harness in yours?

I tried grounding out the fan switch and nothing.
I probed the relay plugs at the firewall with the ignition on and the only wires that have 12 volts are the ones I mentioned above, black with a stripe.

But one of the relays connector has a green wire if I remember right, that has about 2 volts or so, kind of weird.

Iam just wondering if this is a problem with my harness swap from the 88 tbi to the 91 s/d harness.

Is there suppose to be power running to the fan at all times??? And the fan just will not come on until it trips that temp sender in the block, or
Does the power, hot wire stop at the relay on the fire wall, then when it trips the sensor, does it send the power to the fan? I know the switch grounds the circuit but was wondering were the power wire (hot) stops at.

I probed those fan connectors at each fan and there is no power.

am I making sense???
Thanks
Scott

[scott in wa.]

ttt.
Need to know the above,
I plan on working the fan problem, this weekend.


A few more bolts into the torque arm and finish installing the B&M mega shifter and it will be on the road again.
I went from 2:73 to 3:73 I wonder how much of a difference that will make.
Should be interesting.

Thanks
Scott

[aaron_sK]

[Twilightoptics]

I'll post about your prob tomorrow more. Heading to bed now, but 2.73 to 3.73 will be a HUGE difference. I picked up 3 tenths in the quarter from 3.23 to 3.73 (and 3.73 still isn't my optimal).

Plus, the 700 has a steeper first gear than the sticks do.

[scott in wa.]

Ya that’s what I thought on the new gears.
I stayed with the 10 bolt.

The other two things that are coming up are.
The four prong plug in the trani has been ripped out, the wires are all messed up.
I think this plug is TCC only.

Since I manually changed the tranni, font pump mods to eliminate this all together, can It be driven with the these wires capped off and not hooked up?

Also on the mega shifter, I see that the instructions mention a radio shack relay, will I need this to make it complete? And also will I be able to drive it like this as well.
Thanks
Scott

[Twilightoptics]

[scott in wa.]

Wow thanks man.

I was looking in my GM manuals I have a few.
I found the relays for the fan and they show it on the firewall in the book for the 91. Oh well.

What I couldn't find is that darn connector for the tcc. I guess I need to sit down and spend allot of time in there.

the front pump on the tranny If I remember right is made a specific way to provide oiling to the rear bearing when used with a lock up converter.
When you change to a non lock up converter (we went with a custom made 2,800 rpm stall, non lock up) so we had to modify the front pump to allow the rear tail bearing to get oil. Basically drill a hole and plug another.

The reason we went with a non lock up was we could get (we were told) another 200 to 400 rpms out of the stall speed, we weren’t too interested in MPG at the time. It was along time ago, and my memory isn’t what is use to be.



Thanks for your reply I needed it for this weekend.
Putting breaks on today and oil in the rear-end.
Looks bad A$$ as far as the engine goes, will take some pics this weekend.
Thanks
Again
Scott

[Twilightoptics]

Glad to hear it man.

I haven't seen an SD v8 car. just the TBIs so maybe they put the fan relays up there since the maf relays are gone.

Hopefully you can get that thing dialed in and out to a gathering!