Wanted: New/Used Radiator

#16

The first thing I would check is the oil, look inside the oil cap and pull the dipstick. If the oil looks milky or frothy that might indicate contamination. If you use a service that analyzes your oil take a sample in for examination.

However, it might not show-up in the oil either, the visual test isn't definitive, but since it's one of the easiest I would check that first.

Steve A

#17

The pretty-much-definite test is a combustion gas test.

NAPA (Balkamp) 700-1006. Unfortunately, it's $50, and there's almost no cut for jobber. There may be other folks making a tester like this, but this is the one I know and use.

However, the Test Fluid is pretty cheap. If you can find a way to bubble the gasses in the radiator through the fluid without buying their widget, you can save some bux.

Add'l Test Fluid, NAPA 700-1366, $7.50

If you live in an area that requires emissions testing, a std CO meter can be used to sniff the radiator (cap off) for CO in the cooling system.

#18

[banging head on desk]

Removing the thermostat completely isn't a good test on this engine, because that will *also* not cover the bypass port. You'll need a correct thermostat (the the moveable lower coverplate) installed. Sorry, I don't know what I was thinking.

#19

If after you follow Al's last advice, (install new thermostat w/bypass coverplate) and you still have trouble, your two choices are thus:

Flush radiator with a garden hose (careful, since we now have freezing weather) to see if there is a good flow. Contact Billy in Aspers for a radiator since he has parts cars and little use for them now, and is the closest to you.

A gas radiator has a two row core, and a diesel has a three row core. My dad has a 1970 Impala with a 402 BB Chevy and the radiator went bad, so we put a Maxi diesel rad in it. Almost fit perfectly, no cooling problems.

Radiator problems come along much like cholesteral clogging up veins, It didn't just happen one afternoon!!

On all of my Maxi's I have fixed the radiator cap so there is no pressure (none) and have been running that way for over ten yrs. After I had a car with a bad heater core, I "fixed" all the radiator caps to lessen further potential problems.

Stick your correct new thermostat in (must have the air bleed, if it doesn't drill a 1/16 or smaller hole in it) and observe the tubes looking down in the rad cap hole. If you see a lot of bubbles coming up for longer than 5 or ten minutes the head gasket could be blown or a cracked head. (you need to watch it, don't drive it all over town) They are not famous for that in the least, but any engine can let go if overheated enough.

#20

Wayne, thanks for your reply. I will be flushing out the cooling system this weekend. Actually, the radiator I have in the car now is one I bought from Billy about 1.5-2 years ago. This weekend I'm very curious to find out the real condition of it after we do the flushing with water. But speaking of flushing the radiator out, my dad and I did it already about 2-3 weeks ago when I installed the new thermostat. When I started to get the car back on the road the coolant was a light to medium brown color when you'd pop the radiator cap off after a test drive where the engine was at operating temperature. This was when I first started test driving the car up and down my road after it had been sitting for 8-10 months. Each time I'd come back from the drive and I'd look at the coolant level it would be a medium brown color (like water and dirt combine). I always thought that was real weird. That was at the time when the car's temperature guage would read a little over 1/2 way and I was weary on that being correct. So, my dad and I diagnosed it to be the thermostat and it was. At that time (2-3 weeks ago) we installed a new thermostat (one I bought from AutoZone that was 180 degree) and flushed the cooling system with hot faucet water traveling through a garden hose. When flushing that baby out the brown color kept coming out of the radiator for about 5 minutes until it cleared up to clear water. Something else huh! Then after all that I refilled the car with about 8 quarts of antifreeze and 2-3 quarts of water (run a mix because of it being winter). And after that the car ran great, the temperature guage would run 1/2 way at the highest and sometimes run a little below 1/2. I'm thinking I have my problem fixed for sure given that I changed the thermostat. Then, when going up to town to go to the grocery store with my mom I noticed the temperature guage went up to 3/4. I pulled into the parking lot, got out of the car, popped the hood, and saw I had water around the coolant reservoir tank and surrounding areas such as the black air cleaner and on top of the hood right above the coolant reservoir tank. In addition to all that I see that coolant (a light brown color looking fluid) was leaking on the pavement under the coolant reservoir tank. That happened Monday and that's the last time I've driven the car except for test driving it the next day to diagnose the cooling problem furthur. And during those test drives the car still had great power. If it were to be a blown head gasket, wouldn't you notice somewhat of a loss in power? The exhaust comes out regular, not showing any signs of water or coolant coming out the tailpipe. One of the main reasons I'd like to replace the radiator is because of the medium brown color of the so-called coolant in the car. I just believe the radiator needs to be changed, plus I'd like the coolant to look light green or green when I pop off the radiator cap. This should explain everything. Thanks.

#21

One of the main reasons I'd like to replace the radiator is because of the medium brown color of the so-called coolant in the car. I just believe the radiator needs to be changed, plus I'd like the coolant to look light green or green when I pop off the radiator cap.

Could be your cooling system flush was not that thourough. Was the heater valve open? If it was oil from a failed headgasket you would probably be seeing a creamy mayoniese on the underside of the rad cap, persistently returning even after frequently wiping it clean.

Best way I have found to really flush the cooling system:

Add a bottle of cooling system cleaner, run car as directed.

Buy Prestone $5 flush kit, install* the 5/8" tee on the heater inlet hose (passenger side rearmost hose exiting the head towards the firewall), open heater valve, hook up garden hose, open spigot, flush a good 10 minutes letting the water exit the top and bottom of the radiator (petcock open, rad cap off).

*NOTE: DO NOT cut the heater hose while the system is hot/pressurized!

After, let the rad drain sufficient to allow enough space to add antifreeze. Don't delay, running straight water will promote rust buildup quickly.

#22

TheDieseliminator:

I changed a radiator on a persons car a couple months ago and one of the radiator tanks had a glob of brown mud (rust) in it, about half the size of your fist. I'm wondering if the previous owner ran water in your Maxi for a long time and created a lot of brown mud and some of it settled in the engine block? This reminds me of a tractor my dad had (which had replaceable sleeves) and it had an overheating problem. This was a Case tractor from back in the 1930's (had no thermostat) and it would overheat without doing a great amount of work. It turned out there was brown mud around the bottom end of the sleeves (up maybe 2") and was found when the sleeves were pulled out.

All this to say that when a weird problem pops up I start looking for a weird solution. Could it be possible that if you remove the drain plug on the block (behind the exhaust pipe on the drivers side) you may find that it is plugged up with muck? Just trying to explain running 5 minutes of muddy water coming out?

My next question is can you tell that the coolant is actually circulating? In the past year I had a Chevy truck and a Jeep Cherokee that the water pump impeller actually rusted away and was not pumping water. This is a rare problem, but I diagnosed a similar problem where the water pump impeller was loose enough on the shaft that it would spin...not pumping water (also a Chevy)

When the car overheats is the whole radiator hot or only the top half? If this is the case, then the water is not circulating and is only coming up the top radiator hose to heat up the radiator.

Does it look as if the tubes are clogged up (solder bloom) looking down in the radiator from the cap opening?

It is easy to overlook something relatively obvious or diagnose a problem "out of order" and skip over a problem, to get to that weird solution. Not accusing...just more than a person might run into in even ten years of repairing cars.

#23

TheDieseliminator:

Reread your post for like the fourth time. Just changing the radiator will not make the antifeeze green again, because if it was ever brown, the brown originates in the block, and flushing the block or radiator will not get it out, The engine would have to be rebuilt and have it degreased/cooked out while apart to make it like we wish it were, again. If you could see the stuff in the block it is like brown clay, it would take a scewdriver to scrape it out. Any antirust product on the market can only stop further rust from forming by (pardon my lack of ability to explain it properly, and I know someone is going to correct me) removing the "free" oxygen in the water so the metal does not oxidize (rust). I let the real college graduates perfect my "college of hard knocks" explanation of that story.

A headgasket problem or cracked head may not necessarily reduce power. It depends on what vehicle it is. A diesel (such as a olds) only leaks enough compression to displace the antifeeze into the overflow bottle and cause overheating that way. I'm sure that this is not your problem. Just looking at all facets of the problem.

Hope something helps!!

#24

Wayne, thanks for the info. I'm not overly experienced, so please forgive me. And yes when the car overheats the whole radiator is hot. About the coolant circulating, it does when I have the car running and the radiator cap off. The thing about the coolant is, although it's circulating it happens to have bubbles in it when I watch it flowing. What could that mean? I will have to look into diagnosing the drain plug at the left rear side of the block, it could have an issue there. That's true. It does not look like the tubes are clogged when looking into the top of the radiator. Today, my dad got to looking at the car and we ran it so he could diagnose it. Him being more experienced, I thought he would help to see a problem better than I have checked for over the past few days. He really thinks the head gasket is bad. Also, today I called my local Nissan dealer to get a price on the head gasket and they said they showed 4 different head gaskets. Each one has a different thickness they said, so which is the thickness I should buy given I own an 82 Maxima diesel? If it turns out to truly be the head gasket, I don't want to go buy the wrong factory gasket that's thicker or thinner than it should be. Given the knowledge of these engines on this site, I know I can get that answer here. Thank you.

Salvy

#25

Salvy:
I have only had two maxi engines apart, and neither was over a head gasket. They both had a loose rod, one came out the side of the block. One came from a Vo-Tech school and the other was from a car dealer. I knew they were both bad before I bought them. Both had the valve covers full of "unchanged oil" which reminds me of chocolate pudding.

The Maxi's have different thickness head gaskets according to the FSM. I would suspect it has more to do with how close the piston is to the head going down the assembly line. I would recommend looking in the FSM to see where on the head gasket is marked and buy the exact same thickness gasket, when you get yours off.

Familiarize yourself with the oil pressure operated timing chain tightener in the FSM. I had a head off of a gasser once and I remember either using a thin piece of wood to keep it in place or using a large long screwdriver to push it back in to get the timing chain off. The biggest time saver is getting it already to the point where it would inject fuel on #1 cylinder, finding your timing marks on the balancer and the top gear BEFORE YOU TAKE IT APART. Make sure someone doesn't "help you out" and crank the engine over by mistake...so take the battery cable off. Watch where the cam lobes are on #1 cylinder like in the FSM so things look right on the way together. It only takes a few moments to look at something before you get that feeling when your face feels hot, like when you realize you just deleted some program on the computer.....by accident

Through armchair diagnosis, it may be possible that it is a head gasket. Like I say, the Oldsmobiles I worked on years ago would put out a stream of bubbles because, when it comes up on compression it is about 400 to 450 PSI where on a gasser it is 150 to 200 psi. You would notice that the top radiator hose would have that feeling that it has 15 psi when it is cold or only half warmed up with the bubbles, whereas it would need to be nearly hot to have the top hose feel that hard normally.

Sorry you are having this trouble. Normally they just go and go and the body falls off around it before you even get close to the end.
Wayne

#26

Before pulling the head, invest the $50 and do the combustion gas check.

On soiled coolant: green coolants (most of them, anyway) use silicates as corrosion inhibitors. Silicates coat all surfaces, preventing corrosion from water, and other additives keep the pH neutral to reduce corrosion from electrolysis.

Silicate-based corrosion inhibitors wear out. They're good for about 30k miles and two years, that's it.

Brown coolant can be:

* Mixture of green coolant & orange or pink coolant (the ELC class stuff). In this case, you just have std life coolant now, and you still have to adhere to the two-year changeout schedule. All conventional coolants use glycol for the freeze inhibitor, and there's no problem with mixing them, other than reduced life.

* Rust, and coolant with depleted corrosion inhibitors. This can occur with std or ELC coolants.

* Rust, and in-service-life coolant. Fresh coolant, but stirred-up sediment turns it brown.

Anyone who's done cooling system flushes professionally will concur that once you get a heavy load of rust/sediment in an engine, you'll never have clean coolant again. It doesn't matter how much you flush, it'll never all come out. And the sediment will re-deposit in the heater core (which tends to be the filter of the system, IMO), will etch at the water pump's impeller, and accerates wear of the pump's seal.

If you have a rig whose coolant refuses to stay clear, you just have to live with it, until it's disassembled and cleaned. You might reduce the coolant change interval, but that's only a warm-n-fuzzy.

[There are a whole passel (sp?) of coolant formulations these days, off the top of my head: two different greens (Subaru, Honda, Nissan), blue (Hyundai), violet & red (VW, BMW, Toyota), orange (GM), yellow (Ford, Toyota), pink (Chrysler), etc etc. Some of them can be mixed with no ill effects, others you can mix but then they're no longer ELC and you have to change them sooner.]

Just to throw an add'l variable into the mix: When the corrosion inhibitors break down and rust forms, metal is eroded from everywhere, and the head gasket surface is one vulnerable area. Head gasket seepage is common but does little harm if the volume is low, but seepage can occur with multiple vectors, and the gasket surface can become compromised.

IOW, be prepared to have to surface the head. And you can't take much off a diesel head. I admit that, though I used to read mechical drawings for a living, I can't decode what the FSM has to say on the surfacing limit on page EM-30, Figure EM125, but the text implies a limit of .008".

On the head gasket: The thickness of the head gasket is dependent upon how much the pistons project above the block's deck. There's a procedure on how to check this in the 1982 FSM, pg EM-36-37. Nissan's head gaskets identify their thickness by the number of notches ("grooves") in the front side of the gasket. These ought to able to be identified by looking at the gasket even with the head installed, but I just went out and looked at my engine, and I don't see the notches. I assume that they're under where the PS pump is attached -- can anybody confirm this?

If you can't ID your number of notches, don't order the gasket ahead of time. They're not cheap.

Nissan lists only three thicknesses of head gaskets: 1.12mm, 1.2mm, and 1.28mm (roughly .003" increments). NAPA also lists a fourth thickness: 1.3mm. I don't know why; it's also a different material.

Nissan is not the only mfgr to use multiple head gasket thicknesses. Off the top of my head, I recall Opel 1.9l engines also used them.

#27

Al, I'll definitely do the test with the block fluid before we go disassemble the engine. One of the main eye catchers while the engine is running is the water/coolant bubbles in the reservoir tank. That sign there is a reason why my dad thinks it is the head gasket. Could it be bubbling in the coolant reservoir tank because of the automatic transmission? The bottom of the radiator has two smaller black hoses that run to the auto trans and I'm not sure on what their purpose is? Do both of the smaller black hoses run to the auto trans? And on the actual head, I wasn't expecting at all that I'd have to have it surfaced. If it truly is the head gasket then I guess I'll do what has to be done to the head. On the head gasket, I'll just wait to buy it until I can visually see the old one when the head is removed. I'd like to find out the number of notches the 82 head gasket has so I do know even before the head is removed. Thanks.

#28

the little lower hoses are for the auto trans, im pretty sure the drivers side is into the rad and the passenger side is out

#29

TheDieseliminator wrote:One of the main eye catchers while the engine is running is the water/coolant bubbles in the reservoir tank. That sign there is a reason why my dad thinks it is the head gasket.

It is a good indicator of a head gasket issue, but again it's not a definitive test, I would buy the test kit to verify.

TheDieseliminator wrote:Could it be bubbling in the coolant reservoir tank because of the automatic transmission? The bottom of the radiator has two smaller black hoses that run to the auto trans and I'm not sure on what their purpose is? Do both of the smaller black hoses run to the auto trans?

These trans hoses pass trans fluid into and out of a separate cooler integrated into the radiator assembly. I would find it difficult to believe that this is causing the problem. You could see trans fluid in your coolant or more likely with coolant system pressure you would see coolant in your trans fluid.

TheDieseliminator wrote:And on the actual head, I wasn't expecting at all that I'd have to have it surfaced. If it truly is the head gasket then I guess I'll do what has to be done to the head. On the head gasket, I'll just wait to buy it until I can visually see the old one when the head is removed. I'd like to find out the number of notches the 82 head gasket has so I do know even before the head is removed. Thanks.

If it is a head gasket you'll want to have the head checked to make sure it doesn't need to be surfaced. If it does the shop should pull the pre-chambers before surfacing.

Good luck on this, and sorry to hear about your dilemma.

Steve A

#30

TheDieseliminator wrote:Al, I'll definitely do the test with the block fluid before we go disassemble the engine. One of the main eye catchers while the engine is running is the water/coolant bubbles in the reservoir tank. That sign there is a reason why my dad thinks it is the head gasket.

Hmmm. If you can pull the rad cap and see bubbles *before* the engine is fully warmed up, then the head's going to have to come off. Whether it's a head gasket leak or a corroded gasket surface or even corroded through somewhere (or a crack deep enough to leak) is still up in the air, but on the LD28 and with a lack of hydrolocking (water seeps into a cylinder while the engine is off, and prevents cranking the engine over) and no white smoke out the exhaust, I'd think you're most likely faced with a head gasket issue -- with the possibility of having to have the head surfaced, and look carefully at the top of the block as well.

Could it be bubbling in the coolant reservoir tank because of the automatic transmission? The bottom of the radiator has two smaller black hoses that run to the auto trans and I'm not sure on what their purpose is? Do both of the smaller black hoses run to the auto trans?

Answered by others: yes, those are lines that carry ATF from the torque conveter (the part in an AT that generates the most heat) to a coil of steel line in the radiator, then returns the ATF to the sump of the AT. In extreme conditions (towing up long grades in hot weather with the torque converter unlocked) the trans can dump enough heat into the radiator to make a difference, but not if conditions are mild so I think you can discount the AT cooler as a source. Occasionally, a cooler line will break inside the radiator, but the symptom isn't bubbles, it's oil in the coolant and water in the AT (foamy dipstick).

And on the actual head, I wasn't expecting at all that I'd have to have it surfaced.

On aluminum alloy heads, resurfacing is a given. On cast iron heads, resurfacing is optional, depending upon the surface finish when you clean it off and the degree of warpage.

If you have a leaking head gasket, it'll be the first I (or I venture any of us) has heard about -- granted, a small sample, but the combined ownership mileage of all of us is a decent start at a sampling of common problems. Because none of us has heard of a head gasket failure, I'm worried that we may be overlooking some possibility.

If possible, take a few pics of the block with the head off. Nice to add to our gallery (if we had one).

Look carefully at the old head gasket. If the area where the leak occurs isn't obvious, the generic advice is to have the head pressure tested. More money, I know.

Have you installed an OEM-style thermostat (with the bypass cover)?

>If it truly is the head gasket then I guess I'll do what has to be done to the head. On the head gasket, I'll just wait to buy it until I can visually see the old one when the head is removed. I'd like to find out the number of notches the 82 head gasket has so I do know even before the head is removed. Thanks.[/quote]

I don't think I can generalize about the number of notches in any particular year. I think any year LD28 can use any thickness of gasket, depending upon which head and which piston set is used. Why? I don't know.

NissanDiesel Forums

Wanted: New/Used Radiator

Who is online