Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×
RV Trip Planning Discussions

Go Back   iRV2 Forums > MOTORHOME FORUMS > Class A Motorhome Discussions
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
Thread Tools Search this Thread Display Modes
Old 06-09-2014, 10:15 AM   #1
Join Date: Aug 2013
Posts: 79
Angry 3208 Cat exhaust temp too high Traveing now

On my 36 ft pusher with 3208 Cat engine, I placed my EGT probe in the exaust mainfold right at one of the exaust ports so it is very close to the actual piston and valves, The exaust them when driving on flat ground is about 800-850 degrees, but even when getting on the freeway it goes up to 1250-1350 degrees, when climbing hills, I allways have to shift down a gear or two just to keep the temps below 1,350, I try to stay at no more than 1,250 but it seems impossible to do. The previos owners must have had a similar problem but never knew it because there was no egt gage. I did turn up throttle adjustment to allow more fuel into the engine and increased the hi rpm just a bit to allow it to shift at a higher rpm. I have seen EGT's as high as 1,450 degrees for short periods of time and it is scares me, I don't want melted pistons, the engine has 38,000 miles which is very low and it never gets hot on the coolant gage or oil temperature gages, I think I located the temp sensor for the egt way too close to the actual exaust gas, maybe it should be located just before the turbo and I need to plug existing hole. I am on the road now on a 2,000 mile trip with lots of climbing and any help would be appreciated, I can move the location pretty easily and would appreciate any thoughts on the issue. Muledeer2
Muledeer2 is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free! RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 06-09-2014, 10:20 AM   #2
Join Date: Aug 2013
Posts: 79
I also drive pretty slow, usually 55-59 MPH as I am in no hurry, I climb hills without pushing the rig and usually drop to third or 2nd gear if needed to control temps but they ar still high. climbing in 2nd gear at 20 miles an hour and 1250 degrees with rpm at 2,000.
Muledeer2 is offline   Reply With Quote
Old 06-09-2014, 12:46 PM   #3
Senior Member
wb7auk's Avatar
National RV Owners Club
Join Date: Feb 2012
Location: Spokane Valley, Wa
Posts: 1,987
What is the boost pressure?
1999 Trade Winds 7371 Cat 3126B w/current upgrades
1990 D 250 Dodge Ram Cummins Turbo
wb7auk is offline   Reply With Quote
Old 06-09-2014, 02:06 PM   #4
Senior Member
bluegrassrv's Avatar
Join Date: Sep 2013
Location: Leland, NC
Posts: 166
Turning up the fuel will increase power and increase temps. I would look for a less restrictive exhaust system and make sure the air filter in not restricting flow.
2018 GMC Sierra 3500 Denali Dually
2021 Coachman Freedom Express 321FEDSLE Liberty Edition
bluegrassrv is offline   Reply With Quote
Old 06-09-2014, 08:17 PM   #5
Mr. Hipster's Avatar
Join Date: Jan 2014
Location: Milwaukee area/central Idaho
Posts: 93
Probe should be in the down pipe 6" from the turbo flange.
Mr. Hipster is offline   Reply With Quote
Old 06-09-2014, 08:21 PM   #6
Senior Member
Ford Super Duty Owner
Join Date: Jan 2011
Location: Kitts Hill, OH
Posts: 2,244
if it has a Muffler, I'd swap it out to a straight though muffler.
AND if you still worry about it take some of Your added fuel back out.
(RVM#26) THE U-RV 94 F-700/24 foot U-haul box home built RV
Mekanic is offline   Reply With Quote
Old 06-09-2014, 09:02 PM   #7
Senior Member
National RV Owners Club
Join Date: Jun 2010
Posts: 4,581
FYI I've found backing off the throttle a tad will significantly reduce exhaust temps.
Bob & Sandi, dogs Tasha a Frenchie and Tiki a Skipperkey
SW OREGON 2005 34 foot DolphinLX
If towing: a bright red 2016 Mini Cooper on a tow dolly.
1ciderdog is offline   Reply With Quote
Old 06-09-2014, 09:52 PM   #8
Senior Member
dons2346's Avatar
Country Coach Owners Club
Join Date: Dec 2010
Posts: 7,069
Have you talked to Cat to see what kind of exhaust temps you should be seeing? A lot depends on where you are measuring the temps and if Cat says it is OK then. My opinion is that you are to close to the exhaust port for an accurate reading of temps
dons2346 is offline   Reply With Quote
Old 06-10-2014, 08:21 AM   #9
Join Date: Aug 2013
Posts: 79
No pressure gage for boost, I have yet to find a good one that is accurate 38 ft. from the turbo. Thanks for the reply
Muledeer2 is offline   Reply With Quote
Old 06-10-2014, 08:23 AM   #10
Join Date: Aug 2013
Posts: 79
No Muffler removed it months ago, straight 4" exaust about 4 feet long from turbo to exit. Also has a new air filter.
Muledeer2 is offline   Reply With Quote
Old 06-10-2014, 08:25 AM   #11
Join Date: Aug 2013
Posts: 79
Yep how far can you back off the throttle and still not get a ticket for going too slow, it's a given that reducing throttle will make it cooler.
Muledeer2 is offline   Reply With Quote
Old 06-10-2014, 08:30 AM   #12
Senior Member
mchero's Avatar
Join Date: Mar 2006
Location: Full Time USA
Posts: 2,216
Should the computer on the cat be "watching" EGT's?

I installed an Isspro "turbocator" on my Mechanical Cummins. My new to me 07 CAT C7 has the on-board computer that regulates EGT's & such.
mchero is offline   Reply With Quote
Old 06-10-2014, 08:32 AM   #13
Join Date: Aug 2013
Posts: 79
I am thinking it really too close to the valves and piston, the actually probe is lass than 4" from the exaust valve on one of the cylinders, I think it should be moved closer to the turbo inlet to get a reading of all cylinders combined just before the turbo. Measuring just one cylinder so close is not an indication of what happening in the entire engine. muffler is removed and the exaust is less than 4 feet long 4" diameter, and it has a new air filter, the engine is not intercooled, I think an intercooler for air intake would really help.
Thanks for the common sense response. Muledeer2
Muledeer2 is offline   Reply With Quote
Old 06-10-2014, 08:33 AM   #14
Join Date: Aug 2013
Posts: 79
No computer on this model Thanks
Muledeer2 is offline   Reply With Quote

cat, diesel, egt's

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
1989 Spartan diesel Pusher. abacusblack Class A Motorhome Discussions 11 07-08-2015 02:46 PM
RV travel with a cat John Stott Class A Motorhome Discussions 39 09-07-2014 09:21 PM
Which coolant 3208 CAT crockwood Caterpillar Engine Forum 13 06-24-2014 02:17 PM
Engine Swap Cat Diesel Muledeer2 Class A Motorhome Discussions 6 05-24-2014 12:23 PM
Leaking exhaust manifold bigdog Caterpillar Engine Forum 6 12-26-2013 04:24 PM

» Featured Campgrounds

Reviews provided by

All times are GMT -6. The time now is 02:49 PM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2023, vBulletin Solutions, Inc.