Patrol 4x4 - Nissan Patrol Forum banner

1 - 18 of 18 Posts

·
Registered
nissan patrol gq
Joined
·
48 Posts
Discussion Starter #1
Hey guy,s i have a tb42e which use,s some coolant but the funny thing is it doesn,t leak on preassure test and comes up negative on a t,k head check, doesn,t o'heat, no milk in oil but a little if i do a heap of short runs as soon as it goes on a decent run perfect!! is there any other place these things leak like oil cooler or something like that??? before i bite the bullet and pull the head of hopefully someone can give me a magic answer lol
 

·
Registered
Joined
·
414 Posts
Maybe your welsch plugs at the back of the motor, where your gearbox mounts up. It could be leaking from there, there are 2 or 3 welsch plug on the back, one of mine was stuffed too, and it was only leaking a little bit, barely enough for me to notice it.
 

·
Registered
nissan
Joined
·
377 Posts
try checking the exhuast side welch plugs, and have a real close look at the bottom of the water pump while its running
 

·
Registered
nissan
Joined
·
399 Posts
Replace your radiator cap/
They wear after a while and dont function correctly, causing the excess water into the over flow bottle but it cant suck it back into the radiator.
 

·
Registered
nissan patrol gq
Joined
·
48 Posts
Discussion Starter #7
have preassure tested it for ages no leaks running or not, the cap seems to work ok because it recovers coolant from o'flow bottle thats how i see it uses coolant, also on long drive can smell a really lite smell of coolant burning but heater core seems ok no leaks noticiable
 

·
Registered
nissan gq ti patrol
Joined
·
61 Posts
my 93ti tb42e is doing the exact same thing done every test on it known to man comes up fine on every test and that was 40,000k ago i can only think its the head and shes loosing the coolant out the exhaust side but no one can find the leak. let us know what you come up with.

mark
 

·
Registered
Joined
·
414 Posts
Rusky where abouts are u located? If your close to me i would be more then happy to have a look at it for you, i reckon it would be coming from the welsh plugs, have you looked proparly on the exhaust side, there are about 6 of them the size of a $2 coin, and look behind the engine mount cause there is another one there. If worst comes to worse, chuck a bottle of stop leak in it, i know that stuff is good and will seal it up, worked for me for 2 years with a stuffed welsh plug untill i had them changed.
 

·
Registered
nissan patrol gq
Joined
·
48 Posts
Discussion Starter #10
Hey wogboy just did a 500 k run upto walhalla and all surrounding areas spent most of weekend in lowrange used a good litre of coolant in o'flow but the truck ran perfect didn,t miss a beat no o.heating and did some good hill climbs no milk, no missing or chugging. i am located in mornington vic would really appreciate a second oppinion if your in the local area. I am a motor mechanic by trade myself and cant find the leak for the life of me i,ve tested everything can only think that it,s cracked into an exhaust port and leaks that way otherwise i,m stumped
 

·
Registered
nissan
Joined
·
399 Posts
$10 radiator cap - if that still doesnt work, at least you have a new radiator cap.
Try it, i had the same problem and that was the issue.
 

·
Registered
nissan patrol gq
Joined
·
48 Posts
Discussion Starter #12
cap not that old if it was a cap i would imagine that it wouldn,t recover but it would push coolant out to overflow bottle but it recovers fine drove all day today no wuckas then on the 3 hr drive home it used it then
 

·
Registered
Joined
·
414 Posts
Hey rusky, i use to work as a diesel mechanic and thats why i was willing to look at it for you, but it sounds like you have the knowledge there also and you`ve checked most things out yourself, so you have me a bit stumped on this also. The only thing im thinking is that you are not over filling the over flow bottle are you? If you over fill it, once temperature warms up it will throw the coolant out of the overflow hose as you might know. Other then that, im still thinking its a welsh plug issue. Sorry im never down mornington way, im from the western suburbs in melbourne, 20 mins from cbd, if you happen to be around the area inbox me if you like and we will meet up, i`d be glad to look at it for you and see if i can find the problem. Anyway good luck with it, and keep us informed.
 

·
Registered
nissan
Joined
·
502 Posts
the best way to find a coolant leak is to use the RED coolant that is used in trucks it will leave a chawlky red residue from were the leak is you will be suprized at how many weaping ones there are aswell,
 

·
Registered
nissan patrol gq
Joined
·
48 Posts
Discussion Starter #15
preassure tested today i thought bugger it and cranked the tester up to 20 psi, i thought if something is going to pop it will at that had it on for half an hour then started it no leaks and no rough running grrrrr gunna have to pull the head of guy at local head place says they blow in weird and wonderfull ways obviously only draws coolant into engine somewhere when it,s hot
 

·
Registered
Joined
·
196 Posts
Definitely try replacing the cap. It's such a cheap thing.
I had a similar problem that turned out to be the cap. I discovered the problem by mistake one day when I had started the engine from cold and I was waiting and watching as it warmed up. I heard a 'burp' noise from the radiator cap at it released it's first lot of coolant to the overflow bottle. Then I saw a drip of green from under the cap! The secondary seal was leaking but only when the cap was actually releasing water. This made it very hard to find.
Also - when you're having the leak testing done, the radiator cap the the one component that is not included.
 

·
Registered
Joined
·
161 Posts
I had a TB42e once which had a mystery water getting into the oil problem (not saying thats what YOURs is but may help someone else reading this thread) Turned out to be a core plug leaking, one INSIDE the timing case! Water was running down the gears into the sump.

 

·
Registered
nissan patrol gq
Joined
·
48 Posts
Discussion Starter #18
well bit the bullet starting pulling the beast apart as i went to check tappet clearances and there the problem be a nice little puddle of green sitting on top of the cyl head found a tiny crack between hex head blanking bolt around num 4 leading to a push rod gallery so that exlains why i could'nt fault the coolant loss as it wasn't goin into combustion chamber and crack was small enough to only leak small amounts at full opperating temp. Head off and goin to engine shop tomoz hopefully doesn't break the bank but releived to have found the cause better here at home than up a track in the middle of no where
 
1 - 18 of 18 Posts
Top