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Topic Review (Newest First)
04-22-2005 08:12 AM
1quiknova really the only reason to drill 2 holes, NO BIGGER THAN 1/8" in the base of the stat is so you don't get an air poscket when filling the cooling system, it really has no affect from what i've seen on cooling
04-22-2005 08:07 AM
78 monte Yea,we gotta pass a visual.And the check engine light can't be on.But thats it.
Other than that,they plug it in to the puter which tells Albany that another one just got screwed outta $21.
No sniffer or treadmill on 1995 and down.Now 96 and up ya do,but ya get a free tube of KY with every inspection.
04-22-2005 12:27 AM Could be - heaters make great bypasses and they could very well have used it for that. If they did, your A/C evaporator must use other ductwork or you would be heating your cold air! Sounds like you solved your heat spike problem anyway. You are running @ 180F instead of the 195F so your gauge is responding accordingly. Only problem I could see is if you need to pass smog check, T-stat rating is a pollution control device (modern pollution controlled engines are supposed to run hot), otherwise 180F is fine.
04-21-2005 09:43 PM
78 monte The dealer also told me to flush the heater core.Is that what they use as a bypass??
I know one heater hose comes outta that water box were the stat sits.
But it does have good heat though.
04-21-2005 09:17 PM
gauge fluctuation

I have seen this problem on the 2.5 engine many times before,it is usually caused by a pluged heater core or head gasket problem. I would strart by back flushing the heater core and replacing the stat with one that has not been drilled.
04-21-2005 08:58 PM
78 monte Hey Larry,
I'm having windshield glass cut now and the panhardbar in the rearend straigtened and sleeved and also quarter window hinges machined.
I just started working again about 6wks ago so I'm still catching up befor I can go to town on the car.
04-21-2005 06:29 PM
crazy larry Your better off running an aluminum head on the cool side than the hot side.

the new album out yet?

sup wit da volvo?
04-21-2005 06:21 PM
78 monte Well took it out after it cooled down.Its not heating up then popping down but It took like 6mi befor it came up to were it was gonna run at.And its not running very warm.
My gauge has Cold,then four lines then Hot.It runs between Cold and the first line.Allthough it starts off at about 1/8" befor Cold when ya start it up.

Is it OK to run an aluminum head a little on the cool side??

BTW it is cool today,like 40deg outside.
04-21-2005 03:51 PM
78 monte Well I changed to a 180 stat from a 195 and drilled smaller 3/16" holes in it.So far I took it out after I filled the system back up and it runs alittle cool prolly 150.Is that OK on an aluminum head??
In a few hours I will take it out after it has cooled completely and see what happens.I've got my fingers crossed.
04-21-2005 03:48 PM
78 monte
Originally Posted by johnsongrass1
Shadow's are notorious for guages that read wrong. And tachs that fail. The pre printed circuit boards are to blame.
Well,sometimes the gauges all peg and half the dash lights go out.So I wack it right on the corner and voala!!! :rolleyes
04-21-2005 01:20 PM
johnsongrass1 Shadow's are notorious for guages that read wrong. And tachs that fail. The pre printed circuit boards are to blame.
04-21-2005 11:36 AM
redlightning I am not familiar with your engine.One thing I have seen on a few honda,s is the vanes on the water pump will be rusted to the point of there isn,t much left on them and the water will not circulate well.The test for this that I have found is,the car will overheat with the fans running setting still.Then when you bring the rpm,s up the temp will start to drop(starts to circulate better).Just something I have run across on rare occasion's.
04-21-2005 11:02 AM
Originally Posted by camaroman7d
Willys I see what you're saying but you are acting as if the thermostat is "isolated" from the hot engine water. That is not the case. It is sitting in the engine water so once the water is above the opening temp, it should open. Even if the water just above the stat is cooler. That would throw it off by a few degrees (delay the opening) but should not make the gauge peg before it opens. Could be a combination of things here. Very slow acting thermostat and a plugged bypass. This would make sense. Drilling the holes only cost him a few minutes of his time and it is worth a shot. If it works great, if not the real problem needs to be fixed. They didn't come from the factory with holes drilled in them and they worked.

Trust me, it works just like I described! Has nothing to do with air in the system or type of thermostat in place. Sure the thermostat is sitting in the engine water but the water around the exhaust valve is getting a WHOLE lot hotter sooner than the idle water around the thermostat sensing bulb at the front of the intake manifold. Water temoperature gauges are usually in the head where the water is getting hottest fastest and it reads accordingly, while a thermostat w/o circulation of the hot water past it is ignorant of what is going on. Eventually, there is enough gravity circulation of hot water and conduction through the iron (aluminum) that reaches the thermostat and it responds. If the water isn't overtly circulated past the thermostat, it takes longer time to get it going and you will ALWAYS get that scary peak in water temp just before the thermostat opens. Very scary but doesn't last long enough to do any harm. Happens with ANY thermostat- quick opening or otherwise. That's why they install the bypass at the factory. I first ran into this on my 235 in-line 6 in my '53 Chevy pickup. Bypass was inoperative and every morning my engine water temp would spike to +240F then instantly drop to 180F and stay there the rest of the day. I got around it for a couple of years by turning on the heater, but finally got off my duff and got the bypass working and no problems since. A couple of holes in the thermostat flange doesn't affect how it works but does allow the heating water to reach it and get it to operate as designed. Works fine but just not the BEST fix!
04-21-2005 10:08 AM
78 monte KULTULZ,its a 1994 Dodge Shadow.
Well I drilled two holes but I went a bit bigger than 1/8".
I took it for a drive and the temp gauige never came off cold.I let it run in the drive way and it started climbing and reached half on the gauge(1/4 is noramal).Then I took it back out and as soon as air went through the radiator the temp dropped to just above cold.
So I think w/ smaller holes(1/8" like recomended)I'll run at normal temp.Its just I have the overheating if I sit in traffic??
I called a dealer and they told me to flush the heater core??I think they just wanted me off the phone.
I saw online that your sposed to purge air outta the water box through a plug on the top of it.I guess this is the highest point in the system and also the stat sits in the front of it.Think there still could be an air bubble at the top of it??Seems unlikely.
04-21-2005 09:59 AM
johnsongrass1 Holes aren't a fix, but a good crutch. And free
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