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need some help from all who can...

 
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climburns  



Joined: 05 Sep 2007
Posts: 10
Location: Norfolk

PostPosted: Tue Nov 27, 2007 5:12 pm    Post subject: need some help from all who can... Reply with quote

ok...my baby runs....she cranks over real quick now.

the timing was fixed and is adjustable to tune to wat i desire.

my problem is that after about 3 minutes of running, the motor hits redline on the temp gauge and she overheats basicly unless i shut it off.

I bled the system from the air bubble in it and all of the coolant hoses are warm which tells me that coolant is flowing. thermostat is new and i believ the water pump is fairly new

could it be the water pump or radiator???

it could be either or but the car only has 68000ish miles on it and most of the stuff is newish....has anyone else had these problems on this 2.0???



she idles a little rough and i pulled the plugs and they were a little fouled but no major damage. i may have a vacuum leak somewhere but i dnt think it would affect my problem to this degree.

whenevr i step on the gas she actually loses rpms and goes to stall out.......why???

during my rebuild i let the injectors soak in a carb cleaner container and then dried them out and put them in.

wat could it be???


please help in anyway you can...i dont feel like buying alot of things that I dont need to when the car is perfectly fine....ideas and comments are much appreciated..thank you.
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Mike924  



Joined: 12 Aug 2004
Posts: 2601
Location: IoW UK

PostPosted: Tue Nov 27, 2007 5:48 pm    Post subject: Reply with quote

I think your car has a number of minor problems, which you need to sort out one at a time.

The first (and worst) is the overheating. I'd suggest you remove the radiator and reverse flush it. You could also remove the thermostat and reverse flush the head. Johnathon1 on this board had his rad rodded out and found it completely sorted his cooling issues.

Once you've got the temperature under control you can start breaking down the remaining problems.
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Khal  



Joined: 26 Sep 2003
Posts: 4872
Location: Sunny and lovely interior BC, Canada

PostPosted: Tue Nov 27, 2007 5:55 pm    Post subject: Reply with quote

climburns wrote:
I'm not sure if the fa wrks because when I removed the wiring i removed the connections to everything so im kinda lost with what conections go to the fan....I thik that is a good point though because the temp. wasnt increasing rapidly it was just very slow and if the fann as wrking then it should help alot.....thnks for that one.......


Did you get the fan working?

climburns wrote:
could it be the water pump or radiator???


Yes. But...

If the water pump had failed, it'd probably be making a pretty ugly noise. Unlikely to be the problem but possible, I 'spose?

Radiators usually leak. It could be blocked... to test that, I guess you'd remove it and pour water in the top and see if it flows out the bottom? There may be an easier way?

EDIT:
Mike924 wrote:
I'd suggest you remove the radiator and reverse flush it.

Yeah, what he said.

EDIT AGAIN:
climburns wrote:
I bled the system from the air bubble in it and all of the coolant hoses are warm which tells me that coolant is flowing.

When did you check the temp. of the hoses? If coolant was flowing and the engine was overheating (or close to it), those hoses would be HOT, not just warm.

Of course, it could also be a blown head gasket... are you losing coolant? Do you have white-ish smoke coming out of the exhaust pipe?
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Rich H  



Joined: 10 Jun 2007
Posts: 2665
Location: Preston, Lancs, UK

PostPosted: Tue Nov 27, 2007 6:33 pm    Post subject: Reply with quote

+1

The hoses would be far too hot to touch! Could you have a duff temp sender? Shut the engine off and dump the coolant pressure (Careful or you'll get scolded!) Pop the air lock bung above the thermostat and stick a thermometer in, see how hot the coolant really is.

My Elise needs a new sender every 6 months.... (Crappy Rover parts!)
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Mike924  



Joined: 12 Aug 2004
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Location: IoW UK

PostPosted: Tue Nov 27, 2007 6:46 pm    Post subject: Reply with quote

Rich H wrote:
The hoses would be far too hot to touch!
+1!!

Rich H wrote:
Shut the engine off and dump the coolant pressure (Careful or you'll get scolded!) Pop the air lock bung above the thermostat and stick a thermometer in, see how hot the coolant really is.
Sounds like a good idea, but not as useful as you might think. You see, when you release the pressure, the water will boil (that's where the pressure comes from). Boiling water has a maximum temperature of 100°C. So whether your car was running normally or overheating, you will always measure a temperature of just below 100°C (212°F). However, if it's overheating you will get a serious amount of steam when you release the pressure (which is why it's a bit dangerous to do this, unless you remove the pressure cap really slowly and wear heavy gloves when doing it).

Rich H wrote:
Could you have a duff temp sender?
Yes... another board member mentioned his temp sender reading too high if the grounds aren't up to scratch... Threee minutes from cold isn't really enough time for the temperature to build up much...

Rich H wrote:
My Elise needs a new sender every 6 months.... (Crappy Rover parts!)
Rover reverse light switches!! Arrgh!
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Rich H  



Joined: 10 Jun 2007
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PostPosted: Tue Nov 27, 2007 8:24 pm    Post subject: Reply with quote

What he said.
The thermometer would tell you if its properly hot or just warm... Mind you the clouds of scalding steam would tell you that...
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gohim  



Joined: 02 Nov 2002
Posts: 4459
Location: Rialto, CA

PostPosted: Wed Nov 28, 2007 4:25 am    Post subject: Reply with quote

First of all, what do you mean byyou got the timing where you want it?

The timing needs to be set where Porsche specifies. Are you sure that you indexed the timing belt correctly, adjusted the timing belt tension corectly, then torqued the tensioner bolt properly?

You can't do an accurate ignition timing set without the engine warm, with the mixture and idle speed set. If you can't run the engine that long how did you set the ignition timing? Did you even use a timing light with the engine idling at the right speed?

And did you set the ignition timing to factory spec using the correct marks?

What did you do for your rebuild? From the way that you have written, I
take it that you reused the old waterpump. Di you bother to check it to make sure that the impeller was intect, and spinning with the shaft, and it was not leaking?

What about the thermostat? Did you install it, and did you install it in the right orientation (is it upsidedown)?

Did the cooling fans turn on? Did they blow air in the right direction (people have connected the cooling fans so they blow in the wrong direction).

What about the headgasket? Did you install it? Supposedly there is a way to install it wrong, and some oil and water passages get blocked.

Have you checked the valve clearances if the head was off, since the head was reinstalled?

Have you checked the spray patterns of the fuel injectors?
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endwrench  



Joined: 07 Dec 2002
Posts: 1631
Location: Victor, Montana

PostPosted: Wed Nov 28, 2007 4:48 am    Post subject: Re: need some help from all who can... Reply with quote

climburns wrote:
my problem is that after about 3 minutes of running, the motor hits redline on the temp gauge and she overheats basicly unless i shut it off.



This is a pretty good sign of a blown head gasket. If the rad was plugged it would heat up at a normal rate (10 -15 minutes at idle) but with a blown gasket this happens much faster. Worse it is blown the faster it will heat. If you decide it is the radiator, PM me. I have a good used one for cheap.

Todd
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joecitizennn  



Joined: 12 Sep 2005
Posts: 2096
Location: no mans land

PostPosted: Wed Nov 28, 2007 6:21 am    Post subject: Reply with quote

Is it possible to try running it without the thermostat? I had a 924S that ran hot and I removed the thermostat, and the temp needle never moved from the cold mark. So I got a porsche-brand thermostat. End of problems. The thermostat that caused the problems was a brand new Napa unit. Just junk. The 924S needs a precise thermostat to maintain the right temp. I dont know much about the thermostats on pre-s 924 cars.
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gohim  



Joined: 02 Nov 2002
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PostPosted: Wed Nov 28, 2007 3:12 pm    Post subject: Reply with quote

I have never seen an engine overheat in three minutes with a blown headgasket.

I suspect the problem could be something more like extreme ignition timing misadjustment, and/or incorrect valve clearance, and/or camshaft timing misadjustment.
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Ozzie  



Joined: 12 Mar 2005
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Location: Townsville, Qld. Australia

PostPosted: Wed Nov 28, 2007 3:30 pm    Post subject: Reply with quote

maybe just a knackered sender or temp gauge
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johnathan1  



Joined: 08 Oct 2007
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Location: Downey, Ca

PostPosted: Wed Nov 28, 2007 4:34 pm    Post subject: Reply with quote

Yea, I think the problem is more likely a bad sending unit/gauge...

Does the engine FEEL like its overheating? Also feel the radiator, it should be just a hot as the engine.
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climburns  



Joined: 05 Sep 2007
Posts: 10
Location: Norfolk

PostPosted: Wed Nov 28, 2007 5:46 pm    Post subject: update Reply with quote

wowzers....thats alot of replies......

for one, the fan works, i bypassed it and hooked it to the battery
it spins the right way

for two, i mean that i can dvance the rpms or lower the rpms by adjusting my distributor, hence advancing the timing or retarding it

for three, it is definately not a blown head gasket...i rebuilt the motor by hand and for as long as ive been wrkin on cars i kno im not that stupid


i will try def. getting the radiator flushed, i thnk thats the best thing to do first and your right...if i solve the overheating problem then the rest is easy....



NEW PROBLEM.....

my cars intake manifold does get hot when it overheats..duh....besides that someone said that it was their EGR valve....

my egr valve is connected to the manifold, however the metal tube goes down to the egr filter and was dry rotted out at the bottom of the filter

therfore its not even being used and is not even hooked up to the exhaust......

all i did was j b weld the bottom of it into a uniform shape.



COULD THAT BE THE PROBLEM???

SHOULD I REMOVE IT???

CAN I PLUG IT AT THE MANIFOLD SOMEHOW???
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Mike924  



Joined: 12 Aug 2004
Posts: 2601
Location: IoW UK

PostPosted: Wed Nov 28, 2007 5:51 pm    Post subject: Reply with quote

If it's letting air into the manifold, it needs to be plugged. Otherwise the motor will run be running lean and could cause valve damage; could eeven be a source of the 'overheating', but it would have to be real bad for that.
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joecitizennn  



Joined: 12 Sep 2005
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PostPosted: Thu Nov 29, 2007 8:47 am    Post subject: Reply with quote

EGR valve must die!!!!!!!!!!!!!!!! Bypass it.
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