Hi, my 2000 4.6L petrol P38 has been losing coolant for quite a while, I just kept topping it up. Today I noticed the temp gauge on the red and when I popped the bonnet there was coolant coming from the back of the engine, and plenty of it! I've had the RAC out and he pressurised the system to see the problem. He thinks it could be the inlet manifold. Any thoughts on this? I can't tackle this myself so it'll be getting recovered to a garage tomorrow. The RAC man didn't seem too optimistic.
Very likely inlet manifold. Could be head gasket but difficult to see. When I found a leak and confirmed it was the inlet manifold I popped a bottle of the dreaded k seal in. Months later not lost a drop and confident it's plugged. If its hg definitely fix. K seal won't work for long. K seal seems fine if the engines not got loads corrosion.
Thanks for that Ratae, it seems there are a myriad of possibilities as to the cause. I'll tell the mechanic the choices,(I'm sure he'll be aware of them), and we'll take it from there.
How do I confirm if its the manifold or HG?
You need a mirror and a light. That makes it sound simpler than it is! The key is to suss out the height the coolant is appearing. The inlet manifold has coolant passages at the back in line with the inlet holes. I pressured the coolant system to 15 psi before it leaked at 10 psi it was fine. It's not difficult to replace the inlet manifold gasket( valley gasket) tbh but my engine head and block was machined and that had meant the manifold angle is slightly wrong hence the k seal fix
ukadamwest
Well-Known Member
there's not a lot of options for coming out of the back of the engine, unless you have LPG with the coolant pipes running between the bulkhead and the block. the majority of coolant pipes run across the front. there are two pipes that run through the bulkhead to the heater matrix if you are standing at the front looking in, they will be on the left.
the inlet manifold is probably the best diagnosis going on that.. its not a difficult job to do yourself. of its the HG, the most common place to go is at cylinder to waterjacket channel if you pull the plugs you'll have one that is clean that has been steam cleaned by water getting into the cyl. most probably cyl 7 or 8
the inlet manifold is probably the best diagnosis going on that.. its not a difficult job to do yourself. of its the HG, the most common place to go is at cylinder to waterjacket channel if you pull the plugs you'll have one that is clean that has been steam cleaned by water getting into the cyl. most probably cyl 7 or 8
Thank you all for the very helpful replies. I've had the car recovered to a very good 4 x 4 garage as I'm unable to attempt any repairs myself as I've recently had an operation and don't really have full mobility yet. I now know what the mechanic will be talking about when he finds the fault. Cheers lads.
ukadamwest
Well-Known Member
about 10 hours of work on stripping down and rebuilding..... and 4 hours doing the lower manifold bolt on number 8 !
martynv8
Well-Known Member
The swear jar was always replenished on that one.
Just a thought, but if it is the head gasket, would there be an obvious water presence in the oil? I checked the oil before the car was taken away and it looked fine.
Not necessarily. Depends where the gasket has blown and how bad it is.
