Heater core question

[RockinRiviDad]

Hello fellas,

I am new to this forum thing. I have a '65 Riviera & I sent her 401 out to the machine shop for a rebuild. I've owed her for about 20 years & shes been sitting for 13ish years. While the engine is out I was gonna pull the heater core thru the firewall. Thats when I learned it doesnt come out that way unless I cut a 1/4 inch around the opening. My question: if I cut it out will the core now be floating/rattling around in the heater box without the metal that I cut to hold it in???

[RivNut]

There are articles on the Riviera Owners Assn. website (link in my signature) that describes both ways of removing the heater core - from the inside and from the outside. The article on engine side removal goes into detail on how to reassmble it so doesn't leak and is not noticeable.

[RockinRiviDad]

I found it RivNut. Thank you very much.

There are articles on the Riviera Owners Assn. website (link in my signature) that describes both ways of removing the heater core - from the inside and from the outside. The article on engine side removal goes into detail on how to reassmble it so doesn't leak and is not noticeable.

[bob71GS]

There are articles on the Riviera Owners Assn. website (link in my signature) that describes both ways of removing the heater core - from the inside and from the outside. The article on engine side removal goes into detail on how to reassmble it so doesn't leak and is not noticeable.

Ed,

Tony Gentilcore from Australia also had a two page color picture step by step in the Nov/Dec 2012 issue of the Riview.

Bob Bonto #277 ROA

Technical Advisor 71-73

[Jim Cannon]

I am in the middle of replacing my heater core right now. I recommend you do it from the inside. You will be able to clean and paint the heater boxes that way. Yes, boxes. There is one inside the other. I found mine to be all rusty inside because Buick only painted the outside of the outer box. The rest was bare steel. Yes, it is more work, but you will be glad you did.

Also, I found the pipes on the new heater core that the heater hoses connect to were too short by about 3/4". I took the old core and the new core to my local radiator shop and they swapped the end tanks for me. This gives me my original heater hose connections again.

Good luck with it.

[RockinRiviDad]

I wish I wouldve heard from u sooner I followed the "thru the firewall" method written up in the ROA website. You were right about the rust, yuck! I had a sever case of rust in my heater box. I cleaned it up as best I could. Anyhow, I have a new heater core now & found the same problem with the shorter inlet/outlet tubes. It turns out there are two diff heater cores, one for Riv's with A/C & one without A/C. My radiator shop was gonna swap ends too. But I found the new one is half inch shorter in overall length. Where did u get your new core from? I might order one from CARS tomorrow. I am pressed for time now with the holidays & my engine schedueled to be done soon. I wanted to clean up the engine compartment. I am considering buttoning up the heater box without the core inside of it & finsh painting the firewall. That way I will have a reason to go thru the dash at a later date and do the thorough cleaning you recommended. How long did it take u to complete the job?

I am in the middle of replacing my heater core right now. I recommend you do it from the inside. You will be able to clean and paint the heater boxes that way. Yes, boxes. There is one inside the other. I found mine to be all rusty inside because Buick only painted the outside of the outer box. The rest was bare steel. Yes, it is more work, but you will be glad you did.

Also, I found the pipes on the new heater core that the heater hoses connect to were too short by about 3/4". I took the old core and the new core to my local radiator shop and they swapped the end tanks for me. This gives me my original heater hose connections again.

Good luck with it.

[RockinRiviDad]

Ed,

Tony Gentilcore from Australia also

had a two page color picture step by step in the Nov/Dec 2012 issue of the Riview.

Bob Bonto #277 ROA

Technical Advisor 71-73

I am so new that was my first issue. His first paragraph had a blurp about going thru the firewall too lol. I figured I was working on the engine compartment & going thru the firewall seemed like a better idea. Good article with the pictures and all. Does every issue of Riview have articles like that?

[Jim Cannon]

I am so new that was my first issue. His first paragraph had a blurp about going thru the firewall too lol. I figured I was working on the engine compartment & going thru the firewall seemed like a better idea. Good article with the pictures and all. Does every issue of Riview have articles like that?

Only if a member takes the time to write it up!

[Jim Cannon]

I wish I wouldve heard from u sooner I followed the "thru the firewall" method written up in the ROA website. You were right about the rust, yuck! I had a sever case of rust in my heater box. I cleaned it up as best I could. Anyhow, I have a new heater core now & found the same problem with the shorter inlet/outlet tubes. It turns out there are two diff heater cores, one for Riv's with A/C & one without A/C. My radiator shop was gonna swap ends too. But I found the new one is half inch shorter in overall length. Where did u get your new core from? I might order one from CARS tomorrow. I am pressed for time now with the holidays & my engine schedueled to be done soon. I wanted to clean up the engine compartment. I am considering buttoning up the heater box without the core inside of it & finsh painting the firewall. That way I will have a reason to go thru the dash at a later date and do the thorough cleaning you recommended. How long did it take u to complete the job?

Sorry I did not see your post sooner. I am on the road this week and next, so not able to do Internet so often. IMHO, the idea that you have the option to removing the heater core from the engine side should be stricken from the record. Buick put out a Dealer Service Bulletin on this job that said go from the inside. If going from the outside was a good way to go, Buick would have suggested it.

All the cores are a bit short in the longest dimension. Don't worry about that. No one else's will be any better. (They are all coming from the same supplier. Does yours have a sticker on it "Made in Mexico"?) Have your radiator shop put the longer heater hose connections from your original core on your new core.

I do not have my Master Chassis Parts Book at hand here in Tenn., but I'm not so sure heater cores came for A/C and non-A/C cars. I will look it up when I get home. (Or someone on the forum with one of my Master Parts Book CDs can look for us.) I think the aftermarket manufacturers just offer up this slightly smaller core (that needs to be shorter to fit in other cars) as an acceptable replacement core for the Riv. If they offered the longer core, it would not fit in those other cars and they would have to stock 2 different cores. Just my suspicion, no proof.

I assume you cut the wire bail that has the double-S shape on it by the tubes? (to get the core out) If you take it out from the passenger side, you don't cut the bail and when you reinstall, it holds the core tight, even the shorter core. If you decide to go in from the passenger compartment later, you can get one of these bails from a parts car. I have one, in fact, that you can have. I don't need it, they don't wear out so they are not in much demand.

I put a piece of thick rubber down at the other end of the core, between the end tank and the heater box, to make sure the hose connection tubes line up with the firewall openings. You can do the same. And then a piece of foam over the end tank with the heater hose connections, so that your firewall cover pushes the core in tight. I don't think it will rattle.

Going from the inside is a big job. I have been interrupted by travel and I took time to clean and paint heater boxes. I am also doing other things while the dash is apart, not just the heater core. It was a full day to take apart. I assume I will need a full day or two to put it all back together, but I have not done it yet. I tend to work slowly and carefully, so as to not break too many other things and create more work for myself! Plus I'm old, so I can't work all twisted up like a pretzel for 8 hours any more like I used to. YMMV.

[Mr Riviera]

If I remember right the parts book says there was only one core used . The aftermarket cores tubes are a little shorter but useable . I enlarge the opening of the box just a tad to allow the hoses to go inside the box a little - makes a cleaner installation and gives you a little more room for the clamp . I have found that if the car is a nice car to start with with little or no rust its ok to go thru the firewall . If the car has rust issues - perhaps its best to go from the inside . The downside of going inside is you have more to worry about as far as breaking anything - it does however give you a chance to clean and lube parts . Its much easier to go in from the firewall and after your done , cant tell it was done that way .

[RockinRiviDad]

I've never worked on a car to this extent. I see a lot of u guys are doing frame offs and going all out. I pray someday I can do the same. As for now, I am happy to get the ball rolling with hopes to just drive the "old girl".

As for rust issues on my car, its not so bad. Yes it has some (especially in that heater box)as all cars do but its been a Cali car. I found the original owners service log in the glove box. It shows it was bought in Huntington Beach. Why do u think is a factor on whether or not to go thru the firewall?

[RivNut]

Take some things into consideration. What is your intent for the car? Are you building it to drive or show? Are you trying to rebuild it and sell it for a profit? If I were you I look at it this way. 1) If, when completed, you can't tell the difference between an outside removal and an inside removal. and 2) the engine is already out of the car and removing a few items from the firewall will give you access to it, then 3) why would you want to have to take the console out and do all that other stuff, as Dick mentions - perhaps break something else - when you wouldn't have to. If you were tearing the interior apart for some other reason, then going through the inside might be better. Remember, going through the inside gives you a chance to lube all the cables ets.

As for rust, I just tried a product from Harbor Freight called Evapo-rust. I'm working on restoring a couple of old family bicycles and letting stuff soak in the Evap0-Rust over night gets rid of all the surface rust. If it's really rusty, let it soak, take it out and scrub the residue off it, and resoak it. The nice thing about the product is that it's environmentally friendly. I used it in the basement garage and it doesn't smell or give off any noxious fumes. Linda couln't tell I was doing anything of the sort. She alwasy recognizes when I open a can of paint thinner or spary WD-40 or PB Blaster on something. When I was finished, I just poured it down the drain. It's 100% friendly to the environment.

Ed

[RockinRiviDad]

Take some things into consideration. What is your intent for the car? Are you building it to drive or show? Are you trying to rebuild it and sell it for a profit? If I were you I look at it this way. 1) If, when completed, you can't tell the difference between an outside removal and an inside removal. and 2) the engine is already out of the car and removing a few items from the firewall will give you access to it, then 3) why would you want to have to take the console out and do all that other stuff, as Dick mentions - perhaps break something else - when you wouldn't have to. If you were tearing the interior apart for some other reason, then going through the inside might be better. Remember, going through the inside gives you a chance to lube all the cables ets.

As for rust, I just tried a product from Harbor Freight called Evapo-rust. I'm working on restoring a couple of old family bicycles and letting stuff soak in the Evap0-Rust over night gets rid of all the surface rust. If it's really rusty, let it soak, take it out and scrub the residue off it, and resoak it. The nice thing about the product is that it's environmentally friendly. I used it in the basement garage and it doesn't smell or give off any noxious fumes. Linda couln't tell I was doing anything of the sort. She alwasy recognizes when I open a can of paint thinner or spary WD-40 or PB Blaster on something. When I was finished, I just poured it down the drain. It's 100% friendly to the environment.

Ed

I like the considerations you've brought up. I have taken the heater core out from the engine side. I bought a new one but, like Jim Cannon has warned, the tubes are shorter and it is shorter in overall length too. I may try his advice of getting a radiator shop to swap the old core end with the right length tubes onto the new core. After speaking with Dick Sweeney he said he opened up the two holes in the heater box where the tubes come out in order to get the hoses on a little better. That might save me a couple buck.

To deal with the rust. I may use some of the chassis paint I bought from KBS-coatings.com Its a three part system to clean the metal, etch it and seal of the rust with a the paint they provide. They claim that their products are 100% eco friendly too.

[RivNut]

Another rust removal technique that requires only some elbow grease and access to your wife's kitchen is to, and I didn't believe this either until I tried it, is to use a folded square of aluminum foil and water. Scrub with the wet aluminum foil and any surface rust will work free. It won't work where raw metal has rusted, just where surface rust has built up on the surface. If the inside of the heater core box was not painted, it might not ever come really clean but you'll get a lot of it. Eastwood also sells a rust converter. Changes rust into a substance that's workable and paintable. Then use their Rust Encapulator to trap it so it won't spread. It seals it from getting any more oxygen.

[RockinRiviDad]

If I remember right the parts book says there was only one core used . The aftermarket cores tubes are a little shorter but useable . I enlarge the opening of the box just a tad to allow the hoses to go inside the box a little - makes a cleaner installation and gives you a little more room for the clamp . I have found that if the car is a nice car to start with with little or no rust its ok to go thru the firewall . If the car has rust issues - perhaps its best to go from the inside . The downside of going inside is you have more to worry about as far as breaking anything - it does however give you a chance to clean and lube parts . Its much easier to go in from the firewall and after your done , cant tell it was done that way .

Ok, it took a few days. But with everyones help this is what the outcome was. I went to two diff radiator shops. One sold me a heater core with shorter tubes and shorter in overall length. As some have mentioned the over length nor the shorter tubes are not an issue. Someone even suggested having the radiator shop unsolder the end caps with the tubes swap the old onto the new core. So I chose to swap the end caps and the radiator shop did a great job at it. They actually only unsoldered the tubes and swap just the tube....genius idea!

So bottom line...there's another option for those of us who run into this issue again. thanks again fellows for the help

[RockinRiviDad]

Another rust removal technique that requires only some elbow grease and access to your wife's kitchen is to, and I didn't believe this either until I tried it, is to use a folded square of aluminum foil and water. Scrub with the wet aluminum foil and any surface rust will work free. It won't work where raw metal has rusted, just where surface rust has built up on the surface. If the inside of the heater core box was not painted, it might not ever come really clean but you'll get a lot of it. Eastwood also sells a rust converter. Changes rust into a substance that's workable and paintable. Then use their Rust Encapulator to trap it so it won't spread. It seals it from getting any more oxygen.

That foil sounds interesting. I'll have to try that on something. There's plenty of rust on our cars regardless of where they have lived most of their lives lol

since i went thru the firewall to pull my heater core i cant get the whole heater tray/box out to give a good cleaning. I bought a similar product like that Eastwood stuff for my frame. Its a three part system. I think I might hit it with that stuff.

[RivNut]

Besides the Evaporust, WD-40 has come out with a new single stage, environmentally friendly, rust removal product. These products are only good for items small enough to be dipped, unless you want to fill the back yard pool with it and roll your chassis into the pool.

Eastwoods vidoes show rust containment in a couple of steps. 1) Rust converter - chemically changes the rust into something that can be worked, and 2) Rust Encapulator - seals what's been cleaned/converted so that no oxygen can get to the metal. "Don't want no Ferous Oxide lurking in the frame looking for some other place to attack."

[RockinRiviDad]

Besides the Evaporust, WD-40 has come out with a new single stage, environmentally friendly, rust removal product. These products are only good for items small enough to be dipped, unless you want to fill the back yard pool with it and roll your chassis into the pool.

Eastwoods vidoes show rust containment in a couple of steps. 1) Rust converter - chemically changes the rust into something that can be worked, and 2) Rust Encapulator - seals what's been cleaned/converted so that no oxygen can get to the metal. "Don't want no Ferous Oxide lurking in the frame looking for some other place to attack."

Lol... Lots of cool products out there. We guys are awesome

[riv2x4]

How long are the inlet/outlet tubes supposed to be? I have a replacement heater core for my 64 w/air, the inlet/outlet tubes are 2.5" long. If they are too short can longer ones be solder on or do you have to change top "tanks" with tubing?

Larry

[RivNut]

Ok, it took a few days............ They actually only unsoldered the tubes and swap just the tube....genius idea!

So bottom line...there's another option for those of us who run into this issue again. thanks again fellows for the help

Here's an answer for the second part of your question.

[RockinRiviDad]

How long are the inlet/outlet tubes supposed to be? I have a replacement heater core for my 64 w/air, the inlet/outlet tubes are 2.5" long. If they are too short can longer ones be solder on or do you have to change top "tanks" with tubing?

Larry

I just measured mine. they are both at 2.75". Mr Riviera (Dick Sweeney) posted in this thread that all new cores have shorter tubes. He bored the holes in the cover that goes over the tubes a little bigger to allow the hoses to slip into the cover a bit allowing him to still clamp the hoses and get enough of the tube so the hose stays on. He states it gives it a cleaner look too.

I took the other route. Someone (sorry guys, i don't remember who it was) suggested having the radiator shop swap the entire end cap with the tubes from the old to the new. Once I told the radiator guys what I wanted he had an apparently similar but easier route. He just unsoldered the tubes alone and only swapped the tubes... Looks good but I haven't installed it to know if it will leak. I am confident I don't have a fitment problem now... Hope that helps

[RivNut]

Looks good but I haven't installed it to know if it will leak. I am confident I don't have a fitment problem now... Hope that helps

This is NOT the time you want to check for leaks. Ask the shop that did the work if they pressure tested it before giving it back to you. If not, do it that way rather than inggo through the hassle of testing it in the car, finding it leaks, and having to go through removing it a second time.

Ed

[RockinRiviDad]

This is NOT the time you want to check for leaks. Ask the shop that did the work if they pressure tested it before giving it back to you. If not, do it that way rather than inggo through the hassle of testing it in the car, finding it leaks, and having to go through removing it a second time.

Ed

Lol...great point...see thats probably why no one has ever accused me of being smart lol...i'm an idiot...i will call the shop

Thx Ed