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Bob & Carol Howald`

Last year while on a trip my transmission temp suddenly went to 300
degrees. I immediatley stopped and checked it out and determined that
the temp was in the normal range around 170. The gage stayed at 300
degrees the rest of the trip. I ordered a new gage from BB and
installed it. After that the temp would go to 250 degrees and stay in
that area. Again I assured myself that the temp was in fact normal
170.Thinking that it could be a bad sending unit in the transmission, I
changed it this week when I had the pan off. I started the coach up and
the transmission temp. went to 230-260 in about 5 minutes. again I
assured myself that temp was in fact normal about 95 degrees just
idling. I rigged up my old gage under the coach at the sending unit
using different wire from sending unit, new ground wire and a hot wire
from the battery. It seemed to give a normal reading at this point.
What do you suspect the problem to be? bad ground at the dash? bad wire
from the sending unit? Any suggestions would be welcome. Thanks Bob
93pt Illinois

rrob@...

Bob this would be a good example of where an IR Thermometer would come in
handy.

Original Message:
-----------------
From: Bob & Carol Howald` rhowald@...
Date: Sat, 21 May 2005 15:13:27 -0000
To: WanderlodgeForum@yahoogroups.com
Subject: [WanderlodgeForum] faulty transmission temp. reading





  Last year while on a trip my transmission temp suddenly went to 300

degrees. I immediatley stopped and checked it out and determined that

the temp was in the normal range around 170. The gage stayed at 300

degrees the rest of the trip. I ordered a new gage from BB and

installed it. After that the temp would go to 250 degrees and stay in

that area. Again I assured myself that the temp was in fact normal

170.Thinking that it could be a bad sending unit in the transmission, I

changed it this week when I had the pan off. I started the coach up and

the transmission temp. went to 230-260 in about 5 minutes. again I

assured myself that temp was in fact normal about 95 degrees just

idling. I rigged up my old gage under the coach at the sending unit

using different wire from sending unit, new ground wire and a hot wire

from the battery. It seemed to give a normal reading at this point.

What do you suspect the problem to be? bad ground at the dash? bad wire

from the sending unit? Any suggestions would be welcome. Thanks Bob

93pt Illinois










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George Lowry

Bob,

The way I was taught to do a quick check of a temp system was to
ground the wire from the gage at the sensor. With it grounded, the
gage should read full scale high. With no connection, it should read
full scale low. With the indication you have, I would hazard a guess
that you have a high resistance short to ground in the wire some
place. Might be easier to run a new wire than to try to find the short.

George Lowry
'95 WBDA 4203 & GM 4106 (for sale)
Spearfish, SD

Bob & Carol Howald` wrote:

> Last year while on a trip my transmission temp suddenly went to 300
> degrees. I immediatley stopped and checked it out and determined that
> the temp was in the normal range around 170. The gage stayed at 300
> degrees the rest of the trip. I ordered a new gage from BB and
> installed it. After that the temp would go to 250 degrees and stay in
> that area. Again I assured myself that the temp was in fact normal
> 170.Thinking that it could be a bad sending unit in the transmission, I
> changed it this week when I had the pan off. I started the coach up and
> the transmission temp. went to 230-260 in about 5 minutes. again I
> assured myself that temp was in fact normal about 95 degrees just
> idling. I rigged up my old gage under the coach at the sending unit
> using different wire from sending unit, new ground wire and a hot wire
> from the battery. It seemed to give a normal reading at this point.
> What do you suspect the problem to be? bad ground at the dash? bad wire
> from the sending unit? Any suggestions would be welcome. Thanks Bob
> 93pt Illinois
>
>
>
>
>
>
> Yahoo! Groups Links
>
>
>
>
>
>
>
>
>

Bob & Carol Howald`

--- In WanderlodgeForum@yahoogroups.com, "rrob@t..."
wrote:
> Bob this would be a good example of where an IR Thermometer would
come in
> handy.
> Rob: That's how I was assuring myself that the temp's were OK.
Great piece of equiptment. Bob 93pt
> Original Message:
> -----------------
> From: Bob & Carol Howald` rhowald@b...
> Date: Sat, 21 May 2005 15:13:27 -0000
> To: WanderlodgeForum@yahoogroups.com
> Subject: [WanderlodgeForum] faulty transmission temp. reading
>
>
> >
>
>
>   Last year while on a trip my transmission temp suddenly went
to
300

> degrees. I immediatley stopped and checked it out and
determined
that

> the temp was in the normal range around 170. The gage stayed at 300


> degrees the rest of the trip. I ordered a new gage from BB and

> installed it. After that the temp would go to 250 degrees and stay
in

> that area. Again I assured myself that the temp was in fact normal


> 170.Thinking that it could be a bad sending unit in the
transmission, I

> changed it this week when I had the pan off. I started the coach up
and

> the transmission temp. went to 230-260 in about 5 minutes. again I


> assured myself that temp was in fact normal about 95 degrees
just


> idling. I rigged up my old gage under the coach at the sending unit


> using different wire from sending unit, new ground wire and a hot
wire

> from the battery. It seemed to give a normal reading at this point.


> What do you suspect the problem to be? bad ground at the dash? bad
wire

> from the sending unit? Any suggestions would be welcome.
Thanks
Bob

> 93pt Illinois

>

>

>

>
>
>
>
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>
>
>
> Yahoo! Groups Links
> >

>

>
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> mail2web - Check your email from the web at
> http://mail2web.com/ .

pattypape

Hey,Let me try an answer, Smile

We are in our second year of ownership, Maybe we are sophomores??
We have learned a little about our 88 FC.
This suggestion may help and contribute for our many silly first
year questions.


I am not an expert gage person, But we ordered a Teleflex oil
temp gage from BlueBird. After replacing the gage the
temp read 250/ 300 degrees.
In talking to Teleflex, we discovered that the original gage
is no longer available. The replacement gage also requires
the replacement of the temp sensor probe, to match the latest gage.
The original BB gage and the replacement gage carry the same BB part
number, but it was not the same gage. After replacing the defective
gage and later the sensor all readings are normal.

If you want a part number, I can dig it up from the pile of
notes and receipts, we have collected.

Bill 88 FC Michigan Still learning



- In WanderlodgeForum@yahoogroups.com, "Bob & Carol Howald`"
wrote:
> Last year while on a trip my transmission temp suddenly went to
300
> degrees. I immediatley stopped and checked it out and determined
that
> the temp was in the normal range around 170. The gage stayed at
300
> degrees the rest of the trip. I ordered a new gage from BB and
> installed it. After that the temp would go to 250 degrees and stay
in
> that area. Again I assured myself that the temp was in fact normal
> 170.Thinking that it could be a bad sending unit in the
transmission, I
> changed it this week when I had the pan off. I started the coach
up and
> the transmission temp. went to 230-260 in about 5 minutes. again I
> assured myself that temp was in fact normal about 95 degrees just
> idling. I rigged up my old gage under the coach at the sending
unit
> using different wire from sending unit, new ground wire and a hot
wire
> from the battery. It seemed to give a normal reading at this
point.
> What do you suspect the problem to be? bad ground at the dash? bad
wire
> from the sending unit? Any suggestions would be welcome. Thanks
Bob
> 93pt Illinois

Bob & Carol Howald`

Bill: That's what I've been thinking. I've called parts and asked
questions about matching the gage with the sending unit. They have
assured me that I have the matched pair. The old gage said transmission
temp. on it but this new one say's engine oil temp and is calibrated
differently on the face. BB say's this is the only temp gage avilable
for the tranny. Iam going to do more looking into it the first of next
week. Send your part # please.. Thanks for the info.. Bob 93pt Ill.

pattypape

Hi Bob,

On our 88FC, we have the ZF transmission. The ZF Trans.temp gage is
very different from the engine oil temp gage and the rear axle temp
gage. I do not know if these part numbers will solve the problem you
are having with your 1993 Transmission gage.

I went through this same discussion with the BB parts people.I even
purchased a Napa temp sensor for the rear axle, based on the
supplier part number, that BB used in 1988.
Again we had the very high temp readings of 250 to 300 degrees.

So, I contacted Teleflex, They have a great web site at
http://www.tflx.com.
The gages and sensors are listed. They have a tech trouble-shooting
guide that makes it easy to isolate the problem. It is a simple
circiut to trace. There is also an issue with the tread size of the
sensors, therefore Teleflex lists four different sensors 1/8, 1/4,
3/8, or 1/2 inch diameter.

These part numbers are for the Cat, the Onan and rear axle oil temp.
BB oil temp gage # 3865334 crosses over to Teleflex # 9153278

The gage supplied by BB is different than the original gage, but
carries the same part number.
The latest gage has a different scale on the face that requires a
sensor change to match the impedance.
Teleflex recommended that, I purchase a Stewart-Warner sensor to
match the gage.
The Stewart-Warner part # is 280EE-F. It comes with three threaded
inserts to fit all thread sizes. After installing the Stewart
Warner sensor, The BB/Teleflex gages reads normal.

It was difficult to find a Teleflex dealer, I purchase gages from
BB, the price is reasonable.
The Stewart-Warner sensor was purchased from a truck parts store.
(e-mail if you need this phone number, they will ship UPS)
West Marine and Boaters World carry some Teleflex items.

Now, our rear axle temp, oil temps, and oil pressures on both the
Cat and the Onan read correctly.

We like the scaling of the original old gage to better read the much
lower axle temp Sad

Hope this helps,

Bill 88 FC, Love the upgrade to an FC,
7.4 mpg last 3500 miles with little Onan time.



--- In WanderlodgeForum@yahoogroups.com, "Bob & Carol Howald`"
wrote:
> Bill: That's what I've been thinking. I've called parts and asked
> questions about matching the gage with the sending unit. They have
> assured me that I have the matched pair. The old gage said
transmission
> temp. on it but this new one say's engine oil temp and is
calibrated
> differently on the face. BB say's this is the only temp gage
avilable
> for the tranny. Iam going to do more looking into it the first of
next
> week. Send your part # please.. Thanks for the info.. Bob 93pt
Ill.
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