Progress on my 7
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Joined: Mar 2006
Posts: 54
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From: Calgary
Progress on my 7
Here's my story thus far:
I finally got to work on resurructing my $600 7, as soon as we got it onto a lift, the first thing that was noticed was an air pump vacuum leak the size of a quarter. (the prev [2nd] owner complained it was overheating, lol) The exhaust was not stock like he was insisting it was, but was basically a staright pipe out of the stock header, very noisy. Took all of that crap off, in went the racing beat exhaust. It ran with minor exhaust leaks at the header but that was fixed.
... I lost all readings on the tachometer
The fun doesn't stop there; the engine only ran for a max of 30 seconds, I pointed out that the level sensor on the rad was slightly bubbling and whistling so my friend went to take it off. That's right, it went up like a geyser... but the coolant was cold!!! Why the hell would it be under pressure after 30 seconds of mild revving?!
I'll post a picture once I find a good host.
Is it normal for the coolant to shoot like that?
I finally got to work on resurructing my $600 7, as soon as we got it onto a lift, the first thing that was noticed was an air pump vacuum leak the size of a quarter. (the prev [2nd] owner complained it was overheating, lol) The exhaust was not stock like he was insisting it was, but was basically a staright pipe out of the stock header, very noisy. Took all of that crap off, in went the racing beat exhaust. It ran with minor exhaust leaks at the header but that was fixed.
... I lost all readings on the tachometer
The fun doesn't stop there; the engine only ran for a max of 30 seconds, I pointed out that the level sensor on the rad was slightly bubbling and whistling so my friend went to take it off. That's right, it went up like a geyser... but the coolant was cold!!! Why the hell would it be under pressure after 30 seconds of mild revving?!
I'll post a picture once I find a good host.
Is it normal for the coolant to shoot like that?
Too old to act my age
Joined: Feb 2005
Posts: 3,164
Likes: 0
From: Tulsa, Ok.
If it only ran for 30 seconds, and built up that much pressure, it may be time for a rebuild. You said the previous owner complained that it was overheating. Sounds like it was overheated, blew the coolant seals, and is getting worse.
Blown coolant seals do not always manifest in the exhaust, sometimes the pressure goes directly into the radiator. Take the rad cap off, start engine. If you have 'champange' bubbles in the radiator, coolant seals are blown. All of the other telltale signs are there.
Too old to act my age
Joined: Feb 2005
Posts: 3,164
Likes: 0
From: Tulsa, Ok.
Have you had it running long enough to warm up? Unless the cooling system is building up the normal amount of pressure as it warms up, and the engine is then shut down, coolant likely will not leak into the chambers. Even fully warmed up, the cooling system is only running 7-15PSI, while the combustion chambers are well over 100PSI, before combustion. After combustion starts, the pressure inside the chambers is much higher.
There is no other explanation for the radiator to build up that much pressure, in such a short time. There almost has to be compression leaking into the cooling system.
A little pressure (7-15PSI) in the cooling system once the engine starts to build heat is normal. A lot, is not.
There is no other explanation for the radiator to build up that much pressure, in such a short time. There almost has to be compression leaking into the cooling system.
A little pressure (7-15PSI) in the cooling system once the engine starts to build heat is normal. A lot, is not.
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