 Minor motor issues, Cylinder Head temp sensor? |
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| JRust |
 Oct 15 2009, 02:09 AM
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#1
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914 Guru  Group: Members Posts: 6,305 Joined: 10-January 03 From: Corvallis Oregon Member No.: 129 Region Association: Pacific Northwest 
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My engine is basically done. Only down side is the Cylinder head temp sensor is on the wrong side. With it being nice & sealed up I hate to pull it apart again. Is there any reason I can't just put a hole on the drives side tin for it? Cover the other hole?
Well??? |
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| type47 |
Oct 15 2009, 06:09 AM
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#2
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Viermeister Group: Members Posts: 4,254 Joined: 7-August 03 From: Vienna, VA Member No.: 994 Region Association: MidAtlantic Region |
Why not? At this point, seems to me to be the only option. Only problem is, isn't the CHT on cylinder #3, the one that gets the hottest? (fuzzy early morning pre-caffinated memory)
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| DNHunt |
Oct 15 2009, 07:04 AM
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#3
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914 Wizard? No way. I got too much to learn. Group: Members Posts: 4,099 Joined: 21-April 03 From: Gig Harbor, WA Member No.: 598 |
I can't see why it would make a difference in the way the car runs since it only affects warm up. Maybe the mixture will stay a tad rich a few seconds longer.
However you will have to jumper a wire to the harness since the spade connector will be on the wrong side. If the car is to enjoy I wouldn't worry about it. If it will be a garage queen CW then you better change it. Dave |
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| gary gartner |
Oct 15 2009, 09:44 AM
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#4
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i know more than a newbie---way less than a guru Group: Members Posts: 239 Joined: 16-December 04 From: Valencia, Ca Member No.: 3,294 Region Association: Southern California |
Excuse me, but how does the CHTS get on thw WRONG side. "I installed the motor backwards just for fun"??????????? (IMG:style_emoticons/default/smoke.gif) Gary |
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| dr914@autoatlanta.com |
Oct 15 2009, 09:46 AM
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#5
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914 Guru Group: Members Posts: 7,842 Joined: 3-January 07 From: atlanta georgia Member No.: 7,418 Region Association: None |
QUOTE(JRust @ Oct 15 2009, 01:09 AM)  My engine is basically done. Only down side is the Cylinder head temp sensor is on the wrong side. With it being nice & sealed up I hate to pull it apart again. Is there any reason I can't just put a hole on the drives side tin for it? Cover the other hole? Well??? I would tap the right pass head and install it in the correct position. All you would have to do is remove the right cylinder cover. Not a big deal |
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| aircooledtechguy |
Oct 15 2009, 10:24 AM
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#6
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The Aircooledtech Guy Group: Members Posts: 1,966 Joined: 8-November 08 From: Anacortes, WA Member No.: 9,730 Region Association: Pacific Northwest |
I wouldn't bother until the motor has to come out or the covers come off for a real reason. The CHT sensor for the EFI does not have to be on #3 to do it's job for the EFI. Cyl. #2 will work just fine and the EFI won't notice the difference. No need to make things harder. . .
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| agentblr |
Oct 15 2009, 10:32 AM
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#7
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Member Group: Members Posts: 303 Joined: 23-January 04 From: Lee's Summit MO Member No.: 1,595 |
QUOTE(gary gartner @ Oct 15 2009, 07:44 AM) Excuse me, but how does the CHTS get on thw WRONG side. "I installed the motor backwards just for fun"??????????? (IMG:style_emoticons/default/smoke.gif) Gary The cylinder heads are identical and were switched during a rebuild....I've seen it few times ! |
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| gary gartner |
Oct 15 2009, 11:28 AM
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#8
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i know more than a newbie---way less than a guru Group: Members Posts: 239 Joined: 16-December 04 From: Valencia, Ca Member No.: 3,294 Region Association: Southern California |
"The cylinder heads are identical and were switched during a rebuild....I've seen it few times !" ' thanks, I've never rebuillt a T4, or any other motor, for that mattter. appreciate the info Gary |
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| ConeDodger |
Oct 15 2009, 11:40 AM
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#9
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Apex killer! Group: Members Posts: 23,580 Joined: 31-December 04 From: Tahoe Area Member No.: 3,380 Region Association: Northern California
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The biggest reason to do this right has been alluded to by others. The #3 cylinder gets the hottest with the stock tin configuration (other cooling systems exist and are reportedly more efficient). If you put the CHT on the #1 #2 side you risk running leaner. Leaner is hotter, and the spiral continues into oblivion. Oblivion by the way makes a loud expensive noise.
The EFI uses that CHT data to decide on injector pulse time. Don't tell your ECU lies. Now is a good time to do it right. (this should be all of our mantras) |
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| JRust |
Oct 15 2009, 12:38 PM
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#10
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914 Guru Group: Members Posts: 6,305 Joined: 10-January 03 From: Corvallis Oregon Member No.: 129 Region Association: Pacific Northwest
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I do plan to put the FI on eventually. I am starting with carbs anyway so it is not getting changed now. I do not want to have him pull the heads again & switch them. I see what you are saying with it affecting the FI & how it runs. It will have a nice set of Dual 40 Webers on it. Maybe at some point it will get FI put back on it. By the time I get to that it will probably have an oil leak of somekind I need to fix anyway (IMG:style_emoticons/default/dry.gif) . Thanks for all the solid advice guys (IMG:style_emoticons/default/biggrin.gif)
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| aircooledtechguy |
Oct 15 2009, 06:17 PM
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#11
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The Aircooledtech Guy Group: Members Posts: 1,966 Joined: 8-November 08 From: Anacortes, WA Member No.: 9,730 Region Association: Pacific Northwest |
QUOTE(ConeDodger @ Oct 15 2009, 10:40 AM) The biggest reason to do this right has been alluded to by others. The #3 cylinder gets the hottest with the stock tin configuration (other cooling systems exist and are reportedly more efficient). If you put the CHT on the #1 #2 side you risk running leaner. Leaner is hotter, and the spiral continues into oblivion. Oblivion by the way makes a loud expensive noise. The EFI uses that CHT data to decide on injector pulse time. Don't tell your ECU lies. Now is a good time to do it right. (this should be all of our mantras) I understand the point you are trying to make, however I could not disagree more. A cooler temp sensor will cause the EFI to run RICHER not leaner because the oHms will be ever so slightly higher on a slightly cooler head. However the engine doesn't even get up to full operating temp before these sensors read near zero resistance and the ECU goes to it's leanest settings. These are not accurate temp sensing devices such as a gauge sender like a Westach or even VDO. They crudely sense heat and lower the oHms of resistance and the ECU leans out as they warm. Even a dead cylinder will create enough heat through friction to begin to lean out the ECU. . . As I've said, the ECU will never know the difference. These old ECUs are not that smart (IMG:style_emoticons/default/smile.gif) |
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| computers4kids |
Oct 15 2009, 07:05 PM
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#12
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Love these little cars! Group: Members Posts: 2,443 Joined: 11-June 05 From: Port Townsend, WA Member No.: 4,253 Region Association: None |
Jamie,
EFI will run richer on warm-up with the sensor on the wrong cylinder. The PO of my 2.0 74 with EFI mixed up the heads when the motor was rebuilt. My solution, was to install a potentiometer in line with the lead that went to the sensor. I adjusted the pot until I was very happy with the way it ran both in the warm-up stage and hot running. Once the sweet spot was found, just remove the pot and measure the resistance. Go to Radio Shack and for a few dollars buy the correct resistor(s). I then inserted the resistor in line to the TS2 and never looked back. If you decide to go with EFI, let me know and I'll mail the POT to you. Now for those of you who will read my comment and start frothing and can't wait to hit the reply button, I know changing the hot running resistance of a TS2 line is like using bailing wire, but it can produce great results. If the motor isn't in the car already, swap the heads...remember, this is a LE. (IMG:style_emoticons/default/biggrin.gif) |
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| JRust |
Oct 15 2009, 11:02 PM
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#13
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914 Guru Group: Members Posts: 6,305 Joined: 10-January 03 From: Corvallis Oregon Member No.: 129 Region Association: Pacific Northwest
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After thinking on it more today. We are going to pull the heads & switch them. Not that big a deal really. Nothing like doing a job a couple times to learn your lesson. I'll be heading up tommorow night to help with it. I'll be taking all my tin up. Along with my nice Allen head screws I got from Mikey914 (Vendor here making all those awesome aftermarket seals & bumper tops (IMG:style_emoticons/default/biggrin.gif) ). I'll post some pics of my motor with it's tin in place tommorow night hopefully. Nothing seems to go that smoothly even though it is getting done.
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