Well after nearly 15 years I own a 3rd gen again. My last one was an 84' Z28 I drove into the ground.

The new/ used one is a 91' RS with the 305 and 5-speed. Seems pretty much all original with 139k on the clock. Apart from a replaced clutch (not sure how long ago but it works well enough and doesn't slip) everything looks like it came with the car to include the alernator. Most everything works but I have identified one problem and I have a few other questions. Here goes:

Biggest problem I have is the fan does not come on. While driving the car runs just fine temp wise. However if it sits for more than 5 minutes the temp rises and approaches the red. I think the problem is related to the fan. Can anyone shed any light on this? Do the fans themselves simply go out or is it a relay maybe?

Cigarette lighter does not work. Fuse?

Oil pressure guage is kind of weird. When cold the needle moves around and travels past the 60 psi mark. Eventually it settles down.

Clutch pick up is in the first 1/2 to 1 inch of travel. Is this typical and/ or can it be adjusted?

What kind of MPG can I expect?

Overall what is the opinion of the 305 TBI motor. Mine has 139k. Is it about to blow or do these last to 200k plus with proper care?

Any other info would be appreciated.

Thanks.

 

305 tbi is a dog lets start thier off the bat. my cigarette lighter dosent work either i havent looked into it. usually its a fuse or switch. and the fans could be one of three things A. in the passanger side head is a fan switch which may be faulty. B. near the battry there is a fan relay that may also be faulty. or C. you could have a bad motor easiest remedy is to hot wire it to see if it runs. me personally since i got rid of my a/c 6years ago i wired both fans hot to a toggle switch in the center console. best thing i ever did

 

oh yes.. ive heard many guys complain about the play in the clutch i dont think theres a way to adjust it.

 

Yeah it's a dog. My 84' Z with the carb'd 305 HO made more power and was faster.

Well I've ruled out the fan, fuses, and relay. Turned the AC on when the temps hit 220 and the fan kicked on and the temps came down. Maybe related to the sending unit? Anyone know where/ how to get at it and check it out?

 

I always wanted a 5 speed 3rd gen with the 190hp L69. Sounds like you really liked that one.

Welcome back to the 3rd gens. I see you have a nice collection of GM cars.

 

Even though it's a slug, it's still a SBC. It'll last forever with proper care. There's plenty of 200k L03s out there.

 

The 84' was actually an auto but is was my first car (high school grad present from dad) and even though i was young and stupid and drove the car into the ground I have some very fond memories. Always had a thing for the 3rd gen.

What can I say I buy American.

Thanks. Another reason to love SBC's. Even when they do break parts are easy to find.

 

I would replace the switch that is installed in the head that turns on the fan. You should be able to get one in any parst store (Advance, Auto Zone, O'Reilleys, NAPA etc). About $7.00 at autozone.

 

What a coincidence. Did this today for the second time since replacing the original switch and it still hasn't fixed the problem. I know the fan is good as are the relays wiring and fusable link but still no luck. I'm running out of ideas here.

 

All i can say is, i Have an 84 Z28 305 HO and i would rather have it than a TB 305, if you have the right carb setup, much much better

as for the fan issue, when i got my car (with only 60 000kms on it, 80,000kms on it now) it had an electric aftermarket cooling fan system installed

the temperature would go up and down like a friggen rollercoaster

so i took it upon myself to find all the original parts and put it back to a clutch fan system, with that and a 195 thermostat in it, the temp stays perfectly even all of the time, even when sitting in HOT traffic

 

the switch that is on the head is just for the temp gauge there should be another one on the intake by the thermostat housing that turns on fan

check if the lighter has power to the back of it if it does than it is just the lighter assembly

the 305's will go forever with regular services but will go further and better with some mods bigger cam bigger injectors timing chain

changing the rear gears will also help didn't the 91's come with 2 series rear end 3;42 or 3;73 is perfect

i know what you mean about third gen's i'm on my fifth one in a row

 

I will answer the question unstead of saying how much of a dog your car is... I noticed the same problem with my 89 Z28, 350 TPI, the temp is fine at cruising but if you get stuck in traffic or idle it increases towards the red. I decided to let it go and see what happens... sure enough right as it hit the red, the fans kicked on and the temp came down. I am assuming that is how it is supposed to be?? I haven't had any trouble with the car or any overheating issues but yes it does get close to the red before the fan kicks on.

 

it is not normal for it to do that.

normal operating temp is 200-220

if it goes higher than that there is a problem even minor
the most common issue with high temps is build-up in the coolant jacket around the cylinders(on higher mile engines) only way to clean that out is to pop out freeze plugs.you can also put in a 165-180 degree thermostat to help but you want to find out how to get the fan to turn on when temp hits 220 (normal)

buddy of mine had full size blazer 305 w/250000 miles put water pump, thermostat,intake gaskets,radiator and heater core yet temp still ran at a comfortable 250. i pulled motor popped out freeze plugs,cleaned out water jackets and put it in my camaro it then ran at 200 all day no problems

 

Well I have since fixed the cooling fan issue. I ended up replacing the coolant fan switch in the passenger side head and the coolant temp sensor on the intake by the thermostat as well as the thermostat and the car runs cool now and the fan kicks in when it get hot.

All the advice I got at thirdgen.org said the coolant fan switch was responsible for turning on the fan at the required time. Changed it out twice with no success. Changed out the one on the intake and the fan works now.

Don't care enough about the lighter for now. Everything else has been fixed replaced and the car runs great except that it burns a little oil. Thanks for the advice.

On all my other GM cars that is how it has worked. Temps will rise in traffic on a hot day but the fans kick in bring it down to nominal and your covered.