Progress Thread Daily Driver.... 89 GT - Uh Oh

The last couple weekends I have had to do some maintenance. The weekend before last I blew a wheel cylinder so I had to do the rear brakes. While it was up in the air I changed the transmission fluid.

Sunday evening the radiator decided to puke coolant all over the place after a 1 mile errand. I had a used OEM brass radiator that someone gave me so I did an emergency radiator swap Sunday night to get me by for the time being.

The last couple days have been in the high 90’s here. Temp gauge has been hovering around half way mark maybe a needle width or two past during my commute home the last couple days which is a bit higher than with the old radiator. With the old radiator it would stay under half. Tonight I went to McDonald’s and in while waiting in the drive thru it the temp gauge creeped up to almost the 3/4 mark.

At what point on the gauge is the car overheating? I am guessing the half way mark is about 200 deg. Is that a correct assumption?
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Yeah, you'll really need to stick an aftermarket gauge in an intake port to get a real number, although if you use the rear ports on the manifold, they run a little bit cooler than the front location where the stock gauge sender is.

If the rad swap is whats causing the overheating, i'd make sure the fins are all clear and straight and make sure there isn't a calcium build-up inside the radiator blocking the passages. A vinegar flush can help remove some of this
Update time.... Lots has been done since the last update. So to start where I left off, the hot weather we were having went away shortly after the last post and the temps dropped in the 70's-80's. Car was staying cool so I set that issue aside for the time being.

I took the week of labor day off. In that time, I re-dyed the dash and console to get rid of the multi shades of beige. I put some Killmat down on the floor pans before I re-installed the carpet. Installing the killmat took way longer that I expected it to.


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So that week ended with me getting the console and dash back together. Not the best pic. Added the carpet back in made the car hard to shift at times as I lost some pedal travel when the carpet went back it. Clutch releases close to the floor now. Seems to work better when cold and gets worse as the car gets hot. Clutch was replaced about 120 ago or there abouts. The fork cover is missing for some reason. I need to ask my friend if he has it. Lots of grime has got in there with the cover being off. Next step on this is putting in a MM firewall adjuster. I have the one I bought for my wife's SN95 before it got totalled so it will get repurposed to the 89.

Around the same time I picked up the last corner light I needed for the car. When I bought the car I started my search for NOS turn signals as marker lights. I finally got all 4. Deals are still out there folks. I have $250 into these and I started my search in April.


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So shortly after I got the interior back together, I notice a clicking sound from the brakes. I have another thread of this. I was working on diagnosing that issue when the original heater core decided to puke its guts out one night after I got home from work. Pretty much right after I buttoned up the dash too. I knew it was a ticking time bomb but I was hoping it would last a bit longer. I pulled it out almost immediately. I think 87+ cars are easier than 4 eyes, but that is my opinion. anyway.....I was a week or so late in getting the brass heater core 5L5 had for sale on Ebay. I knew I should have bought it when I saw it. Anyway, I went on the quest to find a brass replacement or to get my original one re-cored. And there appears that there is only one shop in my area that does that re-core work anymore. They wanted $461 to re-core the heater core:oops: I said:nono:to that. I could understand a couple hundred but not close to 5 bills. I could not justify that and I struck out on finding another brass replacement so I had to go with an aluminum one.

I has taken me a while to get everything back together because I have had to work around all the rain we have been having since the car is outside. It has pretty much rained every day since I pulled the heater core out. I finally finished putting everything back together yesterday on the inside. Well, everything I took off to do the heater core that is.

Now I am going to address the rest of the cooling system before I put it back to daily use. Water pump has been seeping for months. Time to replace that, I have had the replacement for a while now. While I am at it, I ordered a replacement fan clutch as the original one has very little drag when cold. And then I am going to address the radiator. I would love to get the OEM one re-cored and be done with it but with the price of the heater core, I fear I am looking at $900-$1000 to get it done. Sad because this is an OEM 5 speed radiator. Nice piece to have in a mostly original fox. I am going to try the vinegar first and see what that does and then decide if I just buy another plastic one.

I am going to put the car in the garage so I can get all this done quicker. I miss my daily driver.
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Does the original need to be re-cored or just rodded and cleaned up? Big cost difference there and may be worth taking to the radiator shop to find out being its not in the car.
Not sure what the history of the radiator is. I got it free with a set of Saleen springs I bought earlier this year. I stabbed it in a few months back when the plastic one that was in the car decided to let go. There were a couple green spots in a corner and there is calcification inside but it held water so I went with it. Car ran hotter right off the bat and would overheat in stop and go traffic when the temp was 90+. I assume it is weak but you bring up a good point might be a good idea to check to be sure.
Small update, got the new water pump in on Saturday. There was a lot of sediment behind the plate, between the timing cover. That gasket must have been leaking in there for a while. This would explain my leaks. And I do not know if I mentioned it before but this car has underdrive pulley's on it. Well the water pump and crank pulley. Jeff put the stock alt pulley back on because he was having charging issues. I forgot all about the pulleys. This may explain why the car was getting warm in traffic. In addition to the water pump, I got the new fan clutch on. Last piece of the puzzle is the radiator. Unfortunately, I did not have time to drop it off at the shop this morning but I will tomorrow. Yesterday I got my firewall adjuster on and the old quadrant out. Hopefully tonight, I can get the new MM quadrant in. I am going to run the original clutch cable for now even though it is not super smooth when I cycle the cable back and forth. I probably should take it completely off the car and see if I can oil it. Might do that tonight as well.
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Also, I have under drive pillows on my Coupe and zero overheating in traffic. Had them on the car with the engine driven fan and stock radiator on a warmed up 302, They are currently on the car with a warmed up 331 with a Mark VIIi fan and a Fluidyne radiator and zero issues.

I would say that your issues were worn out equipment in the water pump, fan clutch and radiator department.
Alright clutch quadrant and firewall adjuster are done. I took the cable out and lubed it with a graphite spray. I got it freed up pretty good. I think there was a lot of crud binding it up near the clutch fork. I need to find a cheap clutch fork cover as I think the years of running without one is what gummed up the cable.

I took the rad in Tuesday morning on my way to work to get checked. Figured I would have got a call today with what they found but nope. I will have to call tomorrow and see if they have looked at it yet.
$35 to have it checked. Only reason I am doing it is because it’s an original OEM Ford 5spd brass radiator. Id rather run one of those instead of a plastic tank radiator if I can. If it doesn’t pan out I will get a replacement radiator.

I didn’t have any rust in the clutch cable. Just dirt and grime from there being no cover on the end of the cable. I figured it would feel different now that it is cleaned and lubed with a new quadrant but it feels the same as before in my opinion. It’s not bad, it probably feels about the same as my Saleen. I just expected a change for some reason. Had this car had an aftermarket cable I would have replaced it with a MM one after all the trouble I had with the one that came with my Saleen when I bought it.
Well I got the call on Friday. They said the radiator checked out fine. It flowed good and held their pressure test blah blah blah. I said great, please send it back to the shop I dropped it off at and I will get it Monday morning on my way to work. This morning I go to get it and they try and give me someone else's radiator for an early mustang. They called the other shop where they do all the testing and repair, and they could not find it. They said they would look some more and give me a call later. I just got the call a couple minutes ago and said they finally found it and it is in bad shape. $800 to fix it. $560 for a new brass one or $370 for an aluminum plastic tank one. I think I can get an aluminum plastic tank one from Napa for about $225 so that is what I am going to do to get me back on the road.