Coolant leak on top of radiator - suggestions and options? (1 Viewer)

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aim

Joined
Dec 22, 2004
Threads
20
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485
Location
Western MA
BACKGROUND (a whole bunch of rambling random facts that I'm too ignorant to filter :) : 1994 FZJ80, relatively new to me with 165K. Coolant changed 1 month ago, when vehicle became a DD. Coolant last changed summer of 2004 by PO. Coolant was clean, radiator looks to be in decent shape, with some of the bottom fins starting to change color.

COOLANT LOSS during highway trips: none. Coolant loss in town: 1/4 total overflow capacity per day of a lot of short trips. Fresh coolant puddle all the way around the top lip of the radiator and in front of the battery tray (USDS, behind headlight). Bottom edge of top radiator hose wet. New radiator cap.

(ASIDE: In the interest of the 'slippery slope', I will mention that the front of the engine is dry (no coolant or oil leaks), but my valve cover gasket is leaking (oil) in two places on the USPS side (or so I think). The cover around the PCV valve is wet with oil. I will be changing the plugs, wires, cap/rotor and throttle cable in the near future.)

QUESTIONS:

1. Where is the coolant coming from? Better minds than mine suggest o-ring on top of radiator. Is this the only likely source for the leak? Does the hose get wet from the lip or does the whole lip get wet from the hose?

2. Options? Repair? Replace? Study and wait? Give up and buy a Lada? The local radiator shop couldn't get me a radiator for my old *cough* Neon after two tries, so I don't trust them too much.

3. If I'm replacing the radiator, what else should I do while it's out? I am either working on the vehicle in the driveway (New England weather - 1" of ice on the ground, highs of 50 w/rain, lows of 15 w/snow) or 30 miles away in a heated hangar - but I have to pack all my tools and parts and do it all in one day. Being a rather slow wrench, I'm looking for suggestinos of things to replace that I'm removing and/or exposing.
Radiator, many of the hoses (all?), thremostat, belts? PHH while it's drained? water pump? fan clutch? oil pump gasket? Rear wheel bearings?

4. If I'm replacing the hose (why, oh why, did I mess with it when draining/filling the block?), what else should I replace while I'm showering in coolant?

I *did* search, did read the repair/replace threads, but am hesitating to get chilblains if there is a simpler solution. I am slowly baselining the truck, chasing leaks and this *is* mud, though, so I wouldn't be too upset to start replacing stuff ;) I figure that as I'm crawling on top of the engine changing stuff, I'll break the top tank anyhow...

Thank you in advance for your wisdom,

Andre M.
 
If your radiator has the plastic top, those are ticking timebombs anyway. I have seen them seep and I even had one explode on me and make one hell of a mess (under warranty though.) The upper hose tends to start leaking because its losing its seal, meaning its time to be replaced. In my opinion, new hoses and a fluid flush is Job One on any truck when you get it. I would get all the new hoses including the PHH installed, drain and flush the system a couple times with the old radiator, then put the new one on as you are ready to add the final mixture. You have lots of options for a new radiator....I would PM Mud member Waggoner5 here. I spoke with him tonight and he found an excellent source for a brass replacement fit FJ-80 radiator for a nice price in Dallas.

Don't wait for a cooling problem to find you. Go after it and save yourself a lot of agony and money.
 
To cold and wet to go look at my truck but I find it odd that the hose is wet also, not sure how a slow leak in the rad would get up on the hose but strangers things have happened. Leaking fluids on vehicles do funny things.

Any chance of hosing the coolant off and trying to catch it in the act? maybe start it up cold and go through a warm up and cool down and see where ti si comign from, That would help a lot with figuring out what needs to be done. Certainly do not just let it ride, that is a recipe for disaster. If your rad is sludge free, not leaking or corroded no reason to go through the expense and trouble of replacing it.
 
I'd do a full cooling system baseline after confirming the source. Nothing should be done without confirming the source. Hose off the radiator top, even gently brush it clean at that multi - toothed clamping metal seal. Then dry it and start it up and sit there with the throttle jammed at 2000 rpm until you see something start to seep. I suspect it will be either a cracked top tank from some mechanic leaning on it, or the O ring for the same reason. Plastic top tanks get easily damaged with careless underhood work, and they will fail as a result. My brother in law's BMW blew its top tank while having the cooling system serviced (it was idling in the bay) at the BMW dealership. Since they'd been the only ones underhood, they agreed they must have damaged it and replaced it. This construction will last a lifetime if properly cared for. My other bro in law's 80 started weeping from its O ring at about 280k. I put a spare in it and he's got 297k on it now.

So, little point in suggestions on what to do until you pinpoint the leak. Absolutely essential. If you replace the rad, I'd go with Cdan for a stock one.

DougM
 
IdahoDoug said:
So, little point in suggestions on what to do until you pinpoint the leak. Absolutely essential. DougM

Agreed. My prior post was based on him determining that his radiator is in fact leaking at the top. However, the radiator Gary found (Waggoner5) is brass, and that's something to consider over OEM.
 
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I would do all the above except purchasing the radiator. I got mine from radiatorExpress.com, I gambled on not feeding dan with a $450 radiator and got a 3 core brass shipped to my front door for $230 and a new radiator cap. The OEM was just to expensive when I know that I could almost buy one for me and a friend for the price of one. It fit very well and some of the purists will say the sky will fall if not OEM, I thought that you could use another option. Get the hoses from Dan as well as belts and thermostat, so once cooling system has been gone over you won't need to touch it for a good while.


If the price of the OEM rad is notclose to mid 400's I apoligise.
 
Maybe Waggoner5 will post up his connection and approximate price of the radiator......
 
My upper hose had a pin prick hole that leaked on the top tank, only when running/hot, making me think the radiator was bad, new hose, good to go.
 
Mine was $198 picked up at the shop I deal with. I have no clue what shipping would be. 3 core brass, REALLY nice looking, all brackets correct, etc. Kirbys Radiator, Part # CSF2517, 817.838.6722, located in Ft Worth, Texas. I deal with James.
 
Great info about the brass radiators - but turns out to be premature. The main leak was a crack at the bottom of the front end of the top hose. I caught it right when it started. By this morning (first morning without rain!), the leak was clear. The underside of the hood was bathed in coolant and the spray pattern made it obvious. Confirmed by idling for a couple of minutes and seeing coolant flow out. I did scare myself by getting the distributor wet while hosing things off and having it idle rough for a bit :eek:

Why would it crack at the bottom, by the way? Wouldn't the top be more exposed to air/coolant mixture, and isn't the top more stressed by stretching of the hose?

Replacing just the top hose is easy and straightforward and I wouldn't loose much coolant, but if I decide to do more before spring, which rad/heater hoses should I change while I have the block drained? I know about the phh and for some reason it doesn't look all that scary to me (now, the rubber timing plug on the '92, that was fun!), but I am looking for an idea of how many hoses one can change in a day so that I don't have to keep draining the coolant and freezing my a$&. Also, how many new hose clamps in what sizes will I need to replace the :mad: sardine-can clamps on the heater hoses?

And finally, thank you for your thoughtful answers.
 
Man, a cracked hose is an incredibly OLD hose. That's scary old. I agree with your plan to change them all out. Get factory parts for the upper/lower rad hoses, and the big hose below the thermostat, and the heater valve hose that goes toward the driver's side and downward 90 degrees, and the 90 degree that sprouts out of the firewall on the passenger's side of the engine. The other stuff can be handled with bulk hose. Unfortunately, a good fit is tough on the heater hose as it's metric, so you'll be trial fitting various brands. I found some Goodyear bulk hose at AutoZone (P/N 65071) that is 5/8" but way tighter than other brand 5/8's so it fits perfectly on the cruiser. That gets you a 6 foot coil - enough for 2 trucks for about $6 - best deal of the project. For the slightly smaller hoses back against the firewall you'll need to search harder. I bought a hose from an import parts place destined for a BMW that had a long enough straight section to cannibalize. The maker is "Elaplast" from Germany and it's the proper metric size so also an excellent fit. Try a BMW dealer for this hose which is slightly smaller than 1/2" - might be 12mm I.D.? Anyhow, that should get you going. Buy quality clamps - German GEMs are excellent.

I'd also do a chemical flush, and replace with a factory thermostat and gasket while you're in there. Don't overtighten the thermostat bolts.

DougM
 
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