Thread Tools Display Modes
Old 05-13-2010, 03:51 PM   #1
Join Date: Jan 2010
Location: New Carlisle, Indiana
Posts: 48
Year: 1995
Coachwork: carpenter
Chassis: spartan
Engine: 5.9 cummins
Rated Cap: 84
Vibration at Idle

Hi, I have a 1995 carpenter flat nose front engine, 40 ft. bus. It has a 5.9 cummins with 125,000 miles on it. It runs great but at Idle it vibrates the bus. If I take if just off idle it smooths out. I was told that is normal. I was wondering if I can do anything. Maybe get the idle turned up some? Any Ideas?

Thanks MAJ
maj is offline   Reply With Quote
Old 05-13-2010, 03:56 PM   #2
Site Team
crazycal's Avatar
Join Date: Feb 2007
Posts: 4,089
Re: Vibration at Idle

My 86 Intl does the same thing. It drives me nuts at idle. I was going to try to bump the throttle a hair.
I'm hungry!

You Gotta Let Me Fly
crazycal is offline   Reply With Quote
Old 01-23-2011, 06:26 PM   #3
Join Date: Apr 2010
Posts: 14
Year: 1989
Coachwork: Bluebird
Chassis: TC2000
Engine: 5.9
Rated Cap: 45
Re: Vibration at Idle

Ok, I am not an expert, but this is what I found. I bought a set of used 7mm injectors due to a recent head change. I put it back together, and had a very rough running bus. (89 model with 5.9 BTA, and a VE rotary pump).

First make sure all cylinders are firing. Do this with a cold engine, and stay clear of the turbo. Start the engine and feel each exhaust flange. You will notice that each will warm within a minute. Often there is a cold one or two. Make notes on these.

Shut the engine down , remove the injectors from the cold cylinders. Have a shop check them for spray etc. Mine were not spraying, but dripping. You will see this with black smoke in the exhaust too.

6 new injector nozzles, the engine runs like a smooth diesel...

Remember, i am new to diesels, but have many years on Jet engines.
Apacheglen is offline   Reply With Quote
Old 01-23-2011, 07:59 PM   #4
Bus Nut
frank-id's Avatar
Join Date: Nov 2003
Location: Twin Falls, Idaho
Posts: 808
poor Idle

If the engine has glow plugs, remove and check compression. Replace the plugs after noting the compression values. Add a quart of Power service to 20 gallons of diesel fuel. After 250-350 miles, check the compression again. Any increase of compression will be noticed and the idle will be improved. Doing a compression test is very important to check engine condition. Some times I add a quart of water thru the top of the engine with the air cleaner removed. Make the engine turn about 2000 RPM and pour water into engine slowly so engine does not stall. Place an empty paper box at rear end of exhaust pipe to give evidence of removed carbon. Keep engine at 2K rpms for a short time. Allow engine to idle for a couple minutes. This is a quicky tune up. Frank
frank-id is offline   Reply With Quote

Thread Tools
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
idle time mcmasterp Short-Bus Conversion Projects 6 10-15-2011 01:19 PM
Warm Up Idle for Diesel Engine lornaschinske Conversion Tutorials and How-to's 3 09-14-2011 01:08 PM
Vibration and electronics? GoldenGate Conversion General Discussions 12 12-10-2010 09:07 PM
fast idle switch diagnostics frank-id Cummins Drivetrain 2 05-20-2010 11:42 PM
What's a normal idle RPM for a diesel? Ottomobile Conversion General Discussions 1 03-28-2007 09:54 PM

» Featured Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 01:54 PM.

Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2018, vBulletin Solutions, Inc.