1

1987tjs

Active Member
The expansion tank on my 300tdi defender split two weeks ago. I replaced it with another second hand one today, took it for a test drive, got home and it's split again. I had the head tested and the gasket was ok. The only thing I've noticed is with the expansion tank cap off if I Rev the engine it bubbles in the tank, I'm no machinic so don't know if that should happen. Or if it was a dodgy tank again. Before I go a buy a new one is there any thing else I should check.
Cheers.
 
Did you replace the expansion tank cap also.
Who tested your head gasket and what did he test as sounds more head gasket for that sort of pressure.
Is the car overheating on temp gauge
 
It was sniff tested and didn't change colour. To be honest I'm not sure if I used my original cap or the one that came with the second hand tank as they got mixed up. I left it on tick overdoes a good 30mins didn't move above half way on the gauge. And I'd didn't move during the test run of about 30minutes.
 
bubbles in tank is not good. BUT, you'll need to know where its coming from. Its probably the head gasket. But if a sniff test is clear, then where is this air coming from ? has it been bled properly ? water pump seals Ok ?
 
There only bubbles when I Rev the engine. I was thinking exhaust gases so head gasket. But the sniff test was clear. I think I'll take it to a friend of mine see if he's got a sniff tester. Is there anything I can do to check the gasket?
 
Classic 300 head gasket failure normally due a very slight weep from the back of the timing chest right behind the alternator this allows the level to drop over time the engine gets hot and there goes your gasket, this may have not happened in your ownership and the leaky P-gasket may have been changed but the damage has been done.
Only way to be sure is head off and get it tested properly by an engineering firm, use a quality gasket Elring etc.
The P-gasket is about 2 quid.
 
I carry a 12 volt soldering iron, it's been used to plastic weld a split 300 expansion tank in the past, successfully. Just thought I'd say, like .. :)
 
Thanks 4 that Disco 1BFG But as we /well most of us know when you get pressure 9 times out off 10 it's the GASKET that's BLOWN !:eek::eek::eek:

Steve
 
Magicgrotto said:
Thanks 4 that Disco 1BFG But as we /well most of us know when you get pressure 9 times out off 10 it's the GASKET that's BLOWN !:eek::eek::eek:

Steve
Click to expand...

me not understand :confused:

I've never seen bubbles in the exp tank come from anything but a blown HG - but I was giving him the option of the 0.00005% of the times when its them Klingons getting all cranky

And the "like" was agreeing with you :p
 
Look down the pushrod holes and see if the brass bits of the tappet itself are nice and round and not egg shaped, the head bolts can be used up to 5 times iirc.
 
You must log in or register to reply here.

Similar threads

B
Defender 1986 fuel tank leak
Replies
5
Views
373
miktdish
miktdish
S
Coolant leak overflow
2
Replies
25
Views
1K
sierrafery
sierrafery
G
300Tdi coolant issue
Replies
2
Views
475
GilesHarrison
G
M
Pressure in coolant
Replies
2
Views
504
biketeacherdave
biketeacherdave
S
300Tdi coolant leak from Engine block
Replies
12
Views
1K
Singr07
S