# Overheating A15 engine



## 81coupe210 (May 10, 2005)

I have an 81 210 with the A15 motor in it, and it has run hot every since we bought it. It finally overheated the other day when I didnt have the heat on, like just blew off a little steam before I was able to get it over to the side of the road and shut off. So far I have gone through, replaced the thermostat, then entirely removed the thermostat, done multiple flushes of the cooling system with cleaner to get any build up out of the system, hooked a hose up to the system and forced water through to see if it wasnt comign out anywhere, but it seems to flow through the system just fine so i dont think it's blocked up anywhere, and the radiator drains out great so I dont think its a plugged up radiator. I thought maybe it was a radiator hose collapsing when it was up to temp at higher RPM, but I had somebody sit in the car with it warm and run it, and didnt see any problems with the hoses. Car only has 128k miles on it and is in awesome shape other then this one problem. It has maybe 15 minutes of driving before it overheats, and it will stay right at the notch below the H if you leave the heat on while driving it. I'm new to datsuns but not to cars, and am really really baffled by this. Anybody have any suggestions?


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## B11sleeper (Oct 15, 2003)

Your radiator core has deposits, probably too thick to get out with a flush, it may be too bad to 'rod' out also.

I had this exact same problem, car would stay at the proper temp while idling and even driving around town, go out on the highway and after about 10 - 15 minutes nearly all the way into H, then it cools down and everything's cool again, made me batty.

Get a new radiator core and save the headgasket!

if you had a hose collapsing that would be a sign of a severely clogged radiator.


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## 81coupe210 (May 10, 2005)

How much is it usually to get one of these radiators recored? I saw a replacement on ebay for 50 plus 10 shipping... which so far has been the cheapest one I have seen.


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## nizmo559 (Mar 4, 2003)

Does it have a radiator shrowd* (not sure if I spelled that right) thats in good shape not bent or have warps. One of the 510s I owned had a really bad one and cool air was flowing out of the sides not cooling directly to the engine proberly.


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## 81coupe210 (May 10, 2005)

http://cgi.ebay.com/ebaymotors/ws/e...tem=7973125443&category=33602&sspagename=WDVW

There's a link to it, it's actually brand new, looks exactly like the one that's in the car now. Whats the difference between the MT and AT radiators?


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## 510Mods (Feb 21, 2005)

The automatic transmissions are the same except, the bottom few rows are use to cool the trans. You will see two connector at the bottom of it for the lines.

Also, I believe your overheating due to the head gasket failing on you. It will last for awhile if you try to not overheat alot. It only takes a month of overheating or so and your head will warp. These motors are notorious for overheating and blowing head gaskets.


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## 81coupe210 (May 10, 2005)

So should I try and replace the head gasket as well? How hard is it to do on these motors, anything special I should know about? Like special tools required? Or can I pop off the valve cover, unbolt the head, replace the gasket, and put it all back together in no time like i can on my VW?


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## 510Mods (Feb 21, 2005)

Usually the head gasket will go cause the head surface warps from the overheating. I would take the head to a shop and have them resurface it ~$100. Then install new head gasket and you should be ok. If its pretty bad, the block surface could be warped also. Who knows, buts thats what I have done for these motors and the "L" ones also.


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