TejasCJ7 Posted September 5, 2015 Share Posted September 5, 2015 Well, I got my 78 CJ7 running good, but was heating up when cruising on the highway.. So I decided to check out the original cooling system. First thing, radiator had broken loose from its supports over the years, next, the PO had taken the thermostat out and the heater hoses were incorrect.. so I took the radiator to the local radiator shop where they tested it and said it was plugged up and they could not solder the supports back on without warping the radiator. So, ordered a new radiator from them for the HD Cooling System which was on the original Sales Order.. I then did the whole enchiliada.. reverse flush, flush heater core seperately and replaced both heater hoses, upper and lower rad hoses, all SS clamps, New thermostat (since there was none) and waited for the new rad to come in. While cleaning the thermostat housing and the head, I discovered a lot of pitting on the surface of the head. I tried to seal it with double gaskets & silicone, Got it all back together Friday evening with new Anti-Freeze and Distilled water, buttoned it up and ran it in place.. All Good.. Then started to take it out of the shop and the radiator that I was sold mounts too low and hits the steering shaft at the lower hose outlet. Could not compare to original as it was at the rad shop. In addition to that, the thermostat housing leaks I am going to take the radiator back on Tuesday and get my money back then order an all aluminum radiator from Radiator Express, But now I need to get a better seal on the thermostat head surface.. Has anyone used Permatex® the Right Stuff® Gasket Maker for this problem?? According to Permatex it will fill in small pitting and variances in surfaces. It is an Elastomer and not rubber and is resistant to most everything but gasoline.. Any input or comments appreciated. I really do not want to take the head off to have this surfaced.. Thanks, TejasCJ7 Quote Link to comment Share on other sites More sharing options...
Administrators Moses Ludel Posted September 7, 2015 Administrators Share Posted September 7, 2015 Post some pics of the head pitting...I have several ideas but would like to see the challenge first. This is iron and likely corroded from time on the sidelines and broken down anti-freeze/coolant. Are the freeze plugs intact? Moses Quote Link to comment Share on other sites More sharing options...
TejasCJ7 Posted September 7, 2015 Author Share Posted September 7, 2015 Moses, The freeze plugs look good and found no leakage when all new stuff was run at full temp.. only leak was from the thermostat housing.. It will probably be next weekend before I get a chance to pull the housing and take some pics.. I have several machine shops that I do business with that could surface the head, but did not antipicate pulling it..When I put the Valve Stem Seals in and pressurized the engine, there was 0 leakdown in this engine.. I really do not want to take it apart.. if I do, I may get creative Your write up on the 280 is interesting.. leave the body just like it is and put that engine with EFI and the QT AWD.. Now that would be different I am going to return the new radiator tomorrow and get the original back.. I am going to try to find an exact match.. or I will call one of my old race car radiator guys and have him make me one with an electric fan like the Flex A Lite that fits exactly.. I will not keep doing the same thing and expect better results!! What is the difference in a center cap and drivers side cap location?? I see both in looking at Radiator Express and other websites.. Mine is a center cap, Can I run either?? I know now, that the PO ran it without a thermostat and probably put well water in it.. the AF concentration was very low,, very pale green.. Also, they added a El Cheapo temp gauge since the one in the speedo evidently quit working.. so I am going to replace all gauges with either SW HD series or Auto Meter.. I will keep the temp gauge as I hate not knowing the exact temp..Fuel level is fuel level, everything must have a number!! Cranky in my old age huh?? or maybe its "Been There Done That" syndrome.. Thanks, Gene Quote Link to comment Share on other sites More sharing options...
Administrators Moses Ludel Posted September 8, 2015 Administrators Share Posted September 8, 2015 Moses, The freeze plugs look good and found no leakage when all new stuff was run at full temp.. only leak was from the thermostat housing.. I think we can do a work-around short of removing the head. If the head comes off, you might consider the 4.6L stroker build...That's another story. It will probably be next weekend before I get a chance to pull the housing and take some pics.. I have several machine shops that I do business with that could surface the head, but did not antipicate pulling it..When I put the Valve Stem Seals in and pressurized the engine, there was 0 leakdown in this engine.. I really do not want to take it apart.. if I do, I may get creative Your write up on the 280 is interesting.. leave the body just like it is and put that engine with EFI and the QT AWD.. Now that would be different This started as a barn find that needed very little. Let's try to keep it that way long enough to amortize the cost of a stroker or other upgrades. If you do the stroker at any point, the THM400 is a nice match. EFI has a variety of advantages that we've discussed, whether the Howell TBI or a Mopar MPI conversion—or your own Mopar EFI from a donor 1991-2006 4.0L if you're handy with wiring...We'll start a new thread/topic if you'd like to continue that discussion! I am going to return the new radiator tomorrow and get the original back.. I am going to try to find an exact match.. or I will call one of my old race car radiator guys and have him make me one with an electric fan like the Flex A Lite that fits exactly.. I will not keep doing the same thing and expect better results!! Just my opinion, but I prefer the factory engine driven fan with a clutch. Much more draw, including good CFM flow at lower engine speeds. There are aftermarket fan clutch and fan upgrades to consider. Even a traditional Flex-A-Lite engine driven fan without the clutch if you can stand the noise factor. What is the difference in a center cap and drivers side cap location?? I see both in looking at Radiator Express and other websites.. Mine is a center cap, Can I run either?? Side cap is a cross-flow radiator. Center cap/top tank is a down-flow radiator. Each works well. The main concern is GPH flow through the core and the surface area of the tubes that provide cooling. The best contemporary radiator is a "dimpled tube" core (example: http://www.detroitradiatorcorp.com/drc/page/ultra-core/). Contrary to myths, the row count is not as significant as the actual radiator GPH flow capacity and tube surface area. I know now, that the PO ran it without a thermostat and probably put well water in it.. the AF concentration was very low,, very pale green.. Also, they added a El Cheapo temp gauge since the one in the speedo evidently quit working.. so I am going to replace all gauges with either SW HD series or Auto Meter.. I will keep the temp gauge as I hate not knowing the exact temp..Fuel level is fuel level, everything must have a number!! That's the source of the iron pitting and the block mud/radiator clogging. Cranky in my old age huh?? or maybe its "Been There Done That" syndrome.. Around our place, the word "project" is forbidden. Between personal interest ventures and a career that has demanded magazine and book projects, my track record includes projects based upon utility needs, reader expectations, nostalgia (i.e., over-optimism) or "let's try something new". That's over a half-century of "projects" dating to my learner's permit days. I do understand...and I have "gotten it". I think...Then there's that 1980 Scout II with Nissan turbo-diesel idea...Oh, well! Thanks, Gene Quote Link to comment Share on other sites More sharing options...
TejasCJ7 Posted September 8, 2015 Author Share Posted September 8, 2015 Moses I can help you find a IH 1980 Scout II with the Nissan Turbo-Diesel I have some pretty good IH connections in this part of the country... (we might both get killed) I actually have a friend with a 75 that called me and wants to sell me his Scout.. I gave him a Terra Top a couple of years ago and now he is through messing with it.. wants it gone.. 345 V8.. if I can get him to part with it for the right price, I will probably buy it.. OK, I am going to get back to reality, although the stroker engine really piques my interest.. I may have to build one just for the heck of it..& with the TH400 & QT with posi F&R..That would be an animal.. I am buying a rusted out jeep with a good 258 in the next couple of weeks.. could be the start of something new...and it would have the MOPART EFI AFTER I get this Jeep running & driving.. I took the radiator back and got the original one back.. i took all the measurements of the core and the OD etc. Which radiator would you recommend? Top Flow or Cross Flow?? Do you have a part number for the best one I can get from Detroit Radiator?? It gets hot down here,, Saturday was 99 with a heat index of 105.. i know as i was working in my shop which has real good air flow and it was still HOT... we will stay hot until mid to late November and the humidity is very high, only 30 miles form ths Gulf.. What are you thinking for the pitting?? Some filler like JB Weld and then resurface it? Have you ever used the Permatex® the Right Stuff® Gasket Maker? I either have or have access to all sort of tools, and am pretty willing to try most anything.. As usual, thanks for your input and advice, Gene Quote Link to comment Share on other sites More sharing options...
Administrators Moses Ludel Posted September 9, 2015 Administrators Share Posted September 9, 2015 Gene...If you have a 258 core, that could be the foundation for a 4.6L build. You'd need a common 4.0L block and head for the balance of the hardware...To be continued. As for radiator, a high quality dimpled tube OE replacement would be great in either configuration. Again, you're mainly concerned about GPH flow (get a high output or "A/C" type radiator) and sufficient fan draw with a shroud. The compression ratio and horsepower of a stock 258 is not difficult to handle. I would be forward leaning with the stroker build in mind. Horsepower equals BTUs (approximately 45 BTUs/horsepower), so plan ahead! Permatex makes epoxy two-part materials. There is one for castings and metal. Like JB Weld, these typically have around 3000 PSI tensile, modest for structural use but adequate as a bonding filler. Post some pictures, I'll go into detail with a range of solutions. Moses Quote Link to comment Share on other sites More sharing options...
TejasCJ7 Posted September 9, 2015 Author Share Posted September 9, 2015 Moses I looked at everything offered on the internet and they all are very reasonable, but most if not all are foreign materials assembled in the USA. I am very famliar with chinese & india metallurgy and none of it is worth a darn.. assemble isn't bad, but metal sucks.. I used to get my race radiators from Griffin or Ron Davis and their quality, while not cheap, is second to none. I called Griffin and they make an exact fit all aluminum, with the trans cooler that will handle up to 400 HP and AC.. It is a 2 row using their standard 1.25" tubes and virtually doubles the factory copper 2 row cooling capacity. They also offer a 1.5" tube but I do not need it for this application.. I am probably going to go with this even though it is double the price of any of the internet imported material assembled in the USA stuff. This way, if (ha ha, when) I submit to the bug you planted in my old feeble brain about the Stroker, I will have sufficient cooling to do anything I want to.. Including a litttle boost.... I really have been thinking about that stroker engine you have on your website and am going to do a bit of studying the whole thing.. It definately would be super with the T400 & QT and Mopar EFI.. I am out of town this weekend so will not have the time to get the pictures until next week, unless I can get it done tomorrow.. I do want you to see them and make a recommendation.. Thanks, Gene Quote Link to comment Share on other sites More sharing options...
TejasCJ7 Posted September 14, 2015 Author Share Posted September 14, 2015 Man I am having a heck of a time getting a "stock" raditor for this 78 Jeep.. Crown offers one that they say is a direct replacement for the HD Cooling, PN: J5361574, but it is 3 row and the original one is 2 row. I do not know if the 3 row would be too close to the fan.. My OEM radiator number is "5357424 m 04 01 78" and is not repairable. I can have a custom direct fit aluminum radiator built and not concerned about the price difference, but wanted to keep the original stock look if possible.. even though the Griffin 2 Row w/ 1.25" tubes would cool hades and be a whole lot better down here in South Texas.. If anyone has any input I would appreciate it as my Jeep is just sitting in the corner looking sad.. If I cannot find one in a week or so, I am pulling the trigger on the Griffin and will just paint it black on top since I am pretty good at painting aluminum.. Thanks, Gene Quote Link to comment Share on other sites More sharing options...
Administrators Moses Ludel Posted September 14, 2015 Administrators Share Posted September 14, 2015 Gene...The A/C radiator is HD Cooling. This should fit. Just make sure that the fan, fan clutch and OE fan will work. Get your hands on a Modine catalog. They are a major supplier of OE replacement radiators. See whether the HD and standard cooling interchange. If you cannot get proof, I have 1981-up Mopar part numbers and an older Modine catalog that may be helpful. Moses Quote Link to comment Share on other sites More sharing options...
TejasCJ7 Posted September 14, 2015 Author Share Posted September 14, 2015 Thanks Moses, I also have a friend who is the local Mopar Parts Manager helping me with the search.. they are a Crown dealer and has access to their inventory.. I am trying to get a core thickness measurement right now to compare to mine. Thanks again, Gene Quote Link to comment Share on other sites More sharing options...
TejasCJ7 Posted September 23, 2015 Author Share Posted September 23, 2015 OK, finally got through last weekend family stuff and been very busy this week through tomorrow.. Then back to the Jeep.. I got the radiator in, Autometer Gauges, Stant Thermostat, Stant Gaskets, new Murray water pump and everything else I need to get this old girl back on the road. Figured if I have it down I might as well replace everything and not have to go back to do the same labor again. BTW, I called an engineer at Permatex and discussed the pitted face of the block and he said to use Ultra Grey and it would seal up the pitting. Do not use a gasket, just the Permatex.. So, unless a customer calls and is in a dire situation (always an emergency in the Oil Field ) , Friday morning is JEEP TIME... Then on to other things on the list... I'll update when i get something accomplished.. Gene Quote Link to comment Share on other sites More sharing options...
Administrators Moses Ludel Posted September 30, 2015 Administrators Share Posted September 30, 2015 The Ultra Grey is very well suited to porosity situations. It was OE on many engines in place of cut or composition gaskets. Stack this sealant at the center of the mating faces and try to envision how much will squeeze across the faces and into the coolant passageway. Try to minimize the overlap to prevent risk of sloughing RTV into the radiator. Sealant can clog tubes. The engineer is right about deleting the gasket. Wire brush away any debris or remaining oxidation...Align parts and begin the bolts. Screw them light finger tight and evenly to flatten the sealant to shape... Let the sealant begin to cure just past the slumping stage before clamping down the bolts to the torque specification. Once cured, this material is reasonably rigid and remains stable. It stays in place. OE use included areas with both oil and anti-freeze exposure...Let us know how this works! Moses Quote Link to comment Share on other sites More sharing options...
TejasCJ7 Posted October 2, 2015 Author Share Posted October 2, 2015 Moses Well, I finally got caught up with my oilfield stuff and had time to work on the Jeep.. I ordered an all aluminum radiator from Radiator Express due to the cost, availability and ease of getting it done. The radiator came and evidently they were out of the raw alum. ones because I got a very high polished aluminum radiator... I kinda hated to put this street rod looking rad in my old CJ cause she might feel bad about her other parts looking shabby Anyhow, i got to work early this morning, 58 degrees here in South Texas for a change.. everything was basically apart and fluid was already drained so got the air tools out and took a medium round brush and got the thermostat housing and head area clean. Cleaned all areas with PPG 501 to get any and all grease or oil off the surface and then applied the Ultra Grey to both halves, inserted a new Stant 180 thermostat and put it together until the edges just swelled out per instructions.. Waited an hour then tightened both nuts.. Installed radiator, new Gates Hoses, Ideal SS Clamps and ran all the coolant (fresh from previous radiator disaster) through paint filters and filled the radiator..l I then went and did some other stuff for about 6 hours I know it says to give it 24 hours, but it was around 85 in the shop so 6 was enough) then cranked her up and ran it up to temp, topped off rad and took her for a spin down a country road,,, Pretty good for an old fart, NO LEAKS and it runs right at 180 but the gauge jumps around so I am pretty sure it is good to go. I have new Autometer Gauges for Temp, Oil & Volts with Jeep logo that will go in tomorrow so will have a solid number.. Plus I will get my heat gun back from my buddy tonight and can check temps in coolant system and cylinder head,.. I am Ok with everything so far and this was the most cost effective fix for now.. If I succumb to the Stroker Disease then I will upgrade everything to a Griffin custom rad with dual Spal fans etc. and FlowKooler water pump.. Here is a picture of the cylinder head pitting. This folks is what well water and most city water will do to your cylinder head.. the housing part had no serious pitting.. the reason for this is the head is heat treated cast iron and the housing is cast aluminum or a pot metal mix.. nasty water is hell on hardened steel or iron.. Use Distilled Water or buy 50/50 if you are unsure.. well water (at my shop) is drinkable, but has high concentrations of iron oxide and sulphur so is very corrosive.. Getting started on cleaning and painting some of the engine parts like the nasty air cleaner... and general stuff tomorrow as well as the gauges.. Thanks, Gene Quote Link to comment Share on other sites More sharing options...
Administrators Moses Ludel Posted October 4, 2015 Administrators Share Posted October 4, 2015 I believe that with all that quality prep work, the Ultra Grey will work, Gene! Pitting is enough to get your attention but should seal. Good job! The heat dissipation from that aluminum radiator could be enough for a stroker, it's all about total horsepower and BTUs. I hold these engine builds to 240-250 horsepower, with a lower compression ratio (8.7:1) and a mild "torque" cam. Low end torque is the trick, I'm not after a racing build... Keep us posted, members will benefit from your tap and well water tips! Distilled water is best, pre-mix can be the alternative. Moses Quote Link to comment Share on other sites More sharing options...
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