Heat Exchanger/Radiator Anatomy

[Angela]

WOW...what a great "reader" with my morning coffee. Thanks guys!! I'm sure I'll read this entire thread a few times during the day because there is so much information here.

I do remember each and every one of those lessons about seized bolts. I even taught an AC technician how to do MikeP's technique about tightening them first. Every time I see that guy, he mentions how valuable that tip was. I was glad to be able to pass something on for a change.

I do have all of the stuff all of you have recommended - the gaskets, the Tef Gel, the never seize, the files described, a MAP gas torch, naval jelly, and on and on. I guess pretty well I'm prepared, anyway.

I do change my zincs on a regular basis, at least once a year whether they need it or not, but I pull them from time to time to check them.

Rob, you said just want I (and I'm sure Pascal) wanted to hear - don't pull it off unless we absolutely have to. I'll take a peek at it - if it looks like I last saw it which wasn't that many outings ago, I am happy with the guts and I'll leave them be.

A little while back, I was reading something Yachtsmanwillie wrote about paint - he was using the Rustoleum brush on paint (not the spray) on some engine parts, and I thought they were just darn purdy! I bought a quart of that and the primer that goes with it. I think I'll use that. It worked for him and one of you said you use the ACE hardware brand equivalent.

[Bill Allen]

I think you'll get a better build up with a brush. I like spray although it can be messy (overspray) since I can get back in all the nooks and crannys. Touch ups not a problem as I keep a can in the engine room. I've never seen alpine green in anything other then a spray can but i've never looked very hard since I'm happy with my engine enamel. I've found most jobs on these engines are horrible till you get started, then most of them are easy although messy. Bill

[MikeP]

My experience with easy outs over many years is that they have a success rate of around 50%. It's the other 50% that is a real problem because when they break - and that's what they do when the process fails- you now have a hardened steel core in the middle of the bolt you are trying to remove.

If you snap one of these bolts, my recommendation would be to drill out the bolt(s), get a helicoil kit of the appropriate size and install the helicoil. I promise you it will be a lot less hassle than a broken easy out and the helicoil will provide a nice new thread for the new bolt.

You will get a lot of opinions re gasket sealer. Remember that the gasket is perfectly capable of sealing on its own. Sealer is used because the mating surfaces are often warped or gouged or otherwise damaged in a way that the gasket can't properly seal against the poor surface. So gasket sealer is, hopefully, "insurance" that any poor/warped surfaces are sufficiently filled.

So the first thing to do when renewing any of this stuff is to check/true the mating surfaces. With the rust that is showing in the pic, it is very likely that the mating surfaces are, at minimum, pitted. It would be best to clean that all up and ensure the mating surfaces are true. If you are careful, this can be done with 220 grit wet/dry paper on a sheet of 1/4" plate glass if the part is small enough to be worked against the paper/glass in a figure 8 motion.

If the part cannot be worked that way, a long file can do the job if used carefully.

THere are a lot of opinions re gasket sealer so I'll give you mine as well!
I have two preferences for gasket sealer on the boat. One is "Perfect Seal" This is nothing more than old school shellac type sealer. The advantage is that it will not harden and it will not glue the parts together. It must be used with a gasket. The other sealer I use is Permatex Motoseal. THis is NOT silicone. Motoseal can be used with or without a gasket. If you use it with a gasket, I suggest you put on some latex gloves, put a glob of motoseal between your thumb and forfinger, and rub it into the gasket on both sides. You're just putting a film on both sides of the gasket. Wait a minute or two and then assemble the part. If you use it without a gasket, use a small paintbrush to paint a thin coat onto the mating parts. Again, wait a couple of minutes and assemble.

I'm confident you will prefer it to the silicone products both for its sealing ability, ease of use, lack of squeeze out, and the much easier disassembly if ever required. It is the same material used by all the motorcycle manufacturers (under their own name like "Hondabond," Yamabond," etc) for factory non gasketed assemblies. Note that most new vehicles use either gaskets with no sealant or sealant with no gasket.
http://www.permatex.com/products/aut...Maker_Grey.htm

[REBrueckner]

"NEVER I REPEAT NEVER USE NEVERSIEZE! unless it is the marine grade neversieze."

I bought some at my marine store several years ago...have no idea if it was 'marine" or not as it's on the boat with the new owner....Does it say "Marine grade" or something similar...how do users know??

[REBrueckner]

Mike's post reminds me my Dad and I used PERMATEX gasket seal with good results for many years...There is a #1 and #2....one remains soft and that's the one we found most useful....I thin its #2, but check....can't remember why I started using red silicone maybe ten years ago....

As Mike also noted, using some latex type gloves with sealant is helpful..the Permatex on skin leaves a residue no matter what you do....

[saltshaker]

"When reassembling, use NEVERSEIZE on the bolt threads"

NEVER I REPEAT NEVER USE NEVERSIEZE! unless it is the marine grade neversieze. the regular neversieze contains disimilar metals that can cause electrolisis in the marine environment. If you cant get the marine grade use the saltwaterproof trailer bearing grease. I don't know why people keep giving out this bad advice. They need to do their reasearch first.

Ditto! I was told years ago not to use Neversieze on the boat. Never even thought of dissimilar metals being an issue with it until a friend pointed it out. One of those things you won't discover until it's too late. I've also used marine grade grease with good results. Make sure you replace those lines for the oil cooler. The fittings look pretty bad and not worth the effort to try and rehab them. A good shop will make them up for you if you don't have the tools to properly do it yourself. MAESCO will do it for a small fee on top of the cost of the hose and fittings.

I noticed you have CT clamps on the hoses. They work great but often don't work too well when you try to reuse them. They seem to get a set in them and when you reassemble everything you end up with leaks. If you have leaks when you are finished, check the hose fittings first. Sometimes you can rotate the clamp and get it to work but most of the time you need to change the clamp.

BTW that heat exchanger is VERY HEAVY! Not familiar with your setup but they are usually awkward to handle and given the weight can be tough to maneuver out of the ER. For that reason alone I would consider hiring a pro who knows what to expect. I tore mine down so they just needed to come in and remove them. They took everything to their shop and did all the work. They reinstalled and all was good as new. Money well spent and no trips to the Chiropractor for me.

[rsmith]

"NEVER I REPEAT NEVER USE NEVERSIEZE! unless it is the marine grade neversieze."

I bought some at my marine store several years ago...have no idea if it was 'marine" or not as it's on the boat with the new owner....Does it say "Marine grade" or something similar...how do users know??

Yes it says Marine its formulated with a mix of metals not to cause electrolisis. If you know how a themocouple works the right combo of metals will generate its own voltage like a battery.
I don't use permatex on the HE gaskets because its a PITA to clean up and will stick the endplates on requiring force to get off. I use the BLUE gasket maker and coat the gaskets with it to prevent wicking from the salt water. Put everything together snug let sit overnight then retighten. Run it and retighten again. HE removal should be done on a max 5 year pm schedule if for no other reason than keeping the bolts freed up.

[rsmith]

" Remember that the gasket is perfectly capable of sealing on its own"

Yes it will seal but in time the salt wicks into the gasket edges and as it does forces the metal plates apart causing more leakage. The key with slowing this down(you can't stop it, its inevitable) it to seal the edges of the gasket material to keep the fibers from absorbing the salt. These fresh water guys just don't understand.LOL

[MikeP]

"Yes it will seal but in time the salt wicks into the gasket edges and as it does forces the metal plates apart causing more leakage."

I agree that leakage/seepage can occur with any gasket that is not of the proper material for what it is trying to seal. EPDM is a commonly used material for salt water gaskets and it will not cause that problem. I keep a roll of it on the boat. But I have no idea if the material supplied in a DD replacement gasket set is EPDM or some other material actually specd for salt water use or not. One would hope so. But that doesn't make it so...

[Angela]

Interesting....I got my DD manual out and found the "exploded view" page. The diagram, as well as the text, indicate that a zinc should be inserted into the inlet side and a pipe plug in that spot on the outlet side. We've always had a zinc in each one - it's how the boat was when we got here; I know...doesn't mean it was right, but it didn't appear obviously wrong to us, either. Anyone know why one zinc is better than two here?