Bus Conversions dot Com Bulletin Board
September 02, 2014, 09:36:16 PM *
Welcome, Guest. Please login or register.

Login with username, password and session length
News: 500 Members as of May 5th, 2006.  Smiley  3,499 Members as of October 21, 2012 Cheesy

   Home   Help Forum Rules Search Calendar Login Register BCM Home Page Contact BCM  
Pages: [1]   Go Down
  Print  
Author Topic: 8V92 & HT755 - Transmission temperature question  (Read 1133 times)
PCC
Sr. Member
****
Offline Offline

Posts: 495


Serving Those Who Have Served


WWW

Ignore
« on: November 28, 2012, 07:06:43 AM »

I noticed recently that the transmission temperature seems to be creeping up close to the engine temperature, and that has never happened before.

The dipstick (not referring to a person this time) tells me that the fluid is up, and low fluid is the only reason I know to effect this change.

The oil is bright (not burned), and the shifting is just like it has always been; runs all day. I do not use my transmission retarder.

I also noticed that both temps (engine and transmission) are running higher (both proportionately increasing above normal when traveling at speeds above 60 MPH), but the engine radiator is full (50/50 mix distilled) - Engine oil is up, and is 40W (low ash).

These changes are new and I want to be sure it is just because the weather is cooler ?!
Logged

For some, patience is a virtue.
Dealing with me, it is required.
Thank God - He is always patient.
lostagain
Hero Member
*****
Offline Offline

Posts: 1526


MC5C




Ignore
« Reply #1 on: November 28, 2012, 07:13:21 AM »

Thermostat (s) sticking closed?

JC
Logged

JC
Invermere, BC
1977 MC5C, 6V92/HT740
PCC
Sr. Member
****
Offline Offline

Posts: 495


Serving Those Who Have Served


WWW

Ignore
« Reply #2 on: November 28, 2012, 07:18:59 AM »

No, I think not the thermostat, because I can run all day at 55 - 60 MPH and never get over 180F

I think the problem is stemming from something in the transmission, but I have no idea so I ask (here) the experts.

Logged

For some, patience is a virtue.
Dealing with me, it is required.
Thank God - He is always patient.
TomC
Hero Member
*****
Offline Offline

Posts: 6751





Ignore
« Reply #3 on: November 28, 2012, 07:49:49 AM »

If your engine is at 180, your transmission will always be higher-around 220. Up to 275 for short periods on the transmission isn't bad. But below 250 is better. 180 is normal for an 8V-92TA. I don't think you have anything to worry about. Good Luck, TomC
Logged

Tom & Donna Christman. '77 AMGeneral 10240B; 8V-71TATAIC V730.
PCC
Sr. Member
****
Offline Offline

Posts: 495


Serving Those Who Have Served


WWW

Ignore
« Reply #4 on: November 28, 2012, 08:16:41 AM »

I have just never seen it, in all the years I have been driving this vehicle, over 160F for the transmission, so when I saw it going up . . .

Climbing a long grade, the engine gets to 200F, but the transmission went there too, and I am not used to seeing it so high.

Thank you - maybe the sensor started working, and I now know the truth.

Proves I look at the dash - at least once per trip !!
Logged

For some, patience is a virtue.
Dealing with me, it is required.
Thank God - He is always patient.
luvrbus
Hero Member
*****
Offline Offline

Posts: 12330




Ignore
« Reply #5 on: November 28, 2012, 08:50:37 AM »

Normal operating temperature for the transmission is 160 to 220 at the sump not the converter the converter can reach 300 degrees max keep it between the lines and you will have no problems fwiw low or high fluid level will cause one to heat also  

good luck
« Last Edit: November 28, 2012, 09:00:16 AM by luvrbus » Logged

Life is short drink the good wine first
PCC
Sr. Member
****
Offline Offline

Posts: 495


Serving Those Who Have Served


WWW

Ignore
« Reply #6 on: November 28, 2012, 01:54:12 PM »

So then allow me to extend my query to the engine temp which runs warmer than (my) normal as I increase the speed over 60, it gets up to 195, when it never used to get over 180.

Am I still within boundaries there, considering 2 stroke 8V92. I went over the Rockies and never got up to 200F, so I am still wanting to be sure - just my breakdown concerns !!

Thank you for your patience with me. I have not changed the overall weight since the Rockies trip.

Logged

For some, patience is a virtue.
Dealing with me, it is required.
Thank God - He is always patient.
Lin
Hero Member
*****
Offline Offline

Posts: 4545

1965 MC-5a




Ignore
« Reply #7 on: November 28, 2012, 03:03:47 PM »

Is there a possibility that your radiators are dirtier than on your Rockies trip?  It is not a bad idea to clean them out once in a while.  Are you talking about the same speed, outside temperature, and toad (if any)?  What bus is this (you may have posted the info, but I missed it)? 
Logged

You don't have to believe everything you think.
PCC
Sr. Member
****
Offline Offline

Posts: 495


Serving Those Who Have Served


WWW

Ignore
« Reply #8 on: November 28, 2012, 05:22:33 PM »

Radiator was just dipped and cleaned, but I will pressure wash it, as that may be something I can do to be sure that something did not get missed - Thank you.

I am an H5-60 Prevost. No significant weight has been added since the Rockies trip, but dust and dirt can be added anywhere along the way.

Logged

For some, patience is a virtue.
Dealing with me, it is required.
Thank God - He is always patient.
buswarrior
Hero Member
*****
Offline Offline

Posts: 3571


'75 MC8 8V71 HT740




Ignore
« Reply #9 on: November 28, 2012, 08:08:32 PM »

Go easy with a pressure washer around the radiator!

You don't want to damage it with high water pressure.

Pressure washers are also good for ruining older double pane windows by forcing moisture where you don't want it.

happy coaching!
buswarrior
Logged

Frozen North, Greater Toronto Area
Ace
Hero Member
*****
Offline Offline

Posts: 1163





Ignore
« Reply #10 on: November 28, 2012, 11:04:39 PM »

You said  your 8v-92 runs normal at 180? I'd be checking the gauge! Mine never runs that here on a cool day in Fl.
190+ depending on speed and thats with a new radiator, hoses and such!
Sounds like your situation is more thermostat than anything else!


Sent from my iPhone using Tapatalk
Logged

Ace Rossi
Lakeland, Fl. 33810
Prevost H3-40
PCC
Sr. Member
****
Offline Offline

Posts: 495


Serving Those Who Have Served


WWW

Ignore
« Reply #11 on: November 29, 2012, 07:18:43 AM »

Gauges are accurate, so maybe I have just been fortunate that my vehicle has been running cool, and now it is normal, unlike me.

Thank you to all for easing my concerns.

Hope to cross paths someday as we travel the highways of the greatest country on earth.
Logged

For some, patience is a virtue.
Dealing with me, it is required.
Thank God - He is always patient.
HB of CJ
Hero Member
*****
Offline Offline

Posts: 1246




Ignore
« Reply #12 on: November 29, 2012, 11:33:54 AM »

Could your gages be giving off bad readings?   Wire connection continunitunity over time will do it?  Are you using a cooolant lube/pH reducer along with the antifreeze and distilled H2o?  You want a very alkaline coolant reading.  If it is not, buildup in the radiator(s) may occur resulting in decreased cooling?  Delo 40 in the Detroit?  Curious how your temperature reading would climb/stabilize at maximum contineous warp speed. (wide open)  I'm concerned that your normal (?) Allision temps may be too low and why.  HB of CJ (old coot)
Logged
Pages: [1]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.18 | SMF © 2013, Simple Machines Valid XHTML 1.0! Valid CSS!