Leaky Radiator - Rough Running

[Stevie]

A few weeks ago I noticed that I was having to top the water up in my 1995 GS300 using about a pint at a time. Sometimes it was OK for days, other times it would lose a lot of water in a few hours, but never more than a pint and a half. It never overheated, however, and always ran fine.

Having found a leak at the bottom of the radiator, I have now booked the car in to have a replacement fitted. Problem is, the engine has now started to run really roughly, as if one of the cylinders was missing. Acceleration is weak and throttle response is really lethargic. It sounds badly mis-tuned.

I am assuming that the leaky radiator has caused the problem - an airlock, maybe. Any ideas?

I'm just wondering if I should expect another large bill when the radiator has been replaced. How safe am I driving to the workshop (about 5 miles)?

I'm a bit miffed because I only had the car serviced a month ago.

Stevie

[Bazza]

hope this isnt the start of LOC fund no.2

lets hope it is only the rad :o

[mudzs]

do's sound a bit iffy dare i say head gasket .

[Scorpion]

Sounds like an air lock,when you fill it up trickle the water in and it will pull the air out.

[ColinBarber]

Sometimes air can build up around the coolant temp sensor which can affect the running.

[Stevie]

All this talk about head gaskets is making my wife feel poorly - we were about to book a summer holiday. I guess we'll put that on the back burner then.

Any other votes for an air lock (pleez!)?

There is no steam coming out of the exhaust, which I would expect with a blown gasket. Also, the temperature gauge has never risen above normal.

But the rough running happens when the engine is cold, too. (Don't know if that is useful information or not.)

Stephen

[GreyBeard]

i don't know if your GS is like my LS, but i would look for:

air coming out of the water header bottle when engine's running. don't always expect water coming out of exhaust as mine didn't when heads warped and gasket blew.

maybe when the engine was overheating, the guage didn't show it (mine didn't, it just sat at the mid-point!) and this could have affected the EMU, so disconnect the Battery for 5 mins (then resave your radio settings afterwards!) and it might run better.

plugs / HT leads?

hope this helps.

[mudzs]

could also be a doggy plug or lead and the radiator problem could just be a coincidence

[jac114]

sounds like air lock.. when you top up the rad have the engine running and see what happens.. should fill the bubbles will come up and water go down ..keep doing this until water stays up .. although if you have found a leak then it will still go down anyway...

craig

[Stevie]

OK - I'll go with the air lock verdict. The car's only leaking very slightly at the moment because I poured some Radweld in to block up the hole (as suggested by the garage). Thanks for all your suggestions (except to those who put the fear of *** into me by mentioning a head gasket).

I'm not going anywhere in the car until I drive it to the workshop on Monday. Better safe than sorry.

[sjrainsford]

Hmmm, radweld. Not a lover of it myself...

Was It a Lexus mechanic that suggested that?

[Stevie]

Well, sj, I was a bit unsure, too. No, it wasn't a Lexus mechanic - it was a local workshop. Actually, they said Barr's Leaks but I could only find Radweld. I assume they will flush it all out when they replace the rad.

[Stevie]

Just to let you know - it was an AIR LOCK!!!

The engine is running fine with a new radiator. -:)

Stevie