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engine running rough because of water somewhere?

Posted: Sun Dec 29, 2013 8:22 pm
by joebuck
My m38 has been running like a top. Had a mechanic tweek my points and it runs like a top. Other day I ran through some water about bumper high. Jeep started running rough after that. Soinds like it is running with choke partial out. It cranks fine but I am thin king I got some water in gas or something. I cut gas line off while jeep was running to maybe burn it out. Hadnt work. Any suggestions?

engine running rough

Posted: Sun Dec 29, 2013 9:33 pm
by billybob
Are you running a civilian distributor? If so may have cracked the cap.

Posted: Mon Dec 30, 2013 7:32 am
by oilleaker1
Pull the distributor cap off and look for water in there. You can blow it out with air to dry it if it's wet. Water droplets on the underside of the cap will mess things up for sure. John

Posted: Mon Dec 30, 2013 8:20 am
by joebuck
Its a stock distributor .military spec.

Posted: Mon Dec 30, 2013 9:01 am
by skyjeep50
Although M-series military vehicles had underwater systems that allowed them to "swim", it was a given that they would need servicing after water immersion even if the systems were in perfect operating condition. If your jeep was under water over the wheel hubs you may also need to check for water infiltration into the axles, propeller shafts, transmission, trans-axle, engine and electrical components such as the voltage regulator. A little water can do a whole lot of bad.

Posted: Mon Dec 30, 2013 3:36 pm
by joebuck
Checked the distributor and all was dry. I didnt stay in watwr but for 50 yards however I did back up. Could water have sucked up through pipe? Motor runs steady except when u punch it , it doesn't have immediate power. It runs like it is flooding. Any more suggestions

engine running rough

Posted: Mon Dec 30, 2013 5:29 pm
by billybob
I hate to be the bearer of bad news but it sounds to me like you may have a crawdad stuck in the tailpipe. Just kidding, hope you find the problem.

Posted: Mon Dec 30, 2013 8:13 pm
by wesk
This is a good point to leave the stab in the dark guess work and start a serious round of step by step troubleshooting and inspection. Get the old troubleshooting pages in the TM open and go through one set of symptoms at a time.

Posted: Tue Dec 31, 2013 8:08 am
by oilleaker1
Wes is correct, it may have nothing to do with the water. I just went through a week of trouble shooting. If you don't have the electrical adaptor test set, you may want to get one. The waterproof electrics make it next to impossible to trouble shoot. No gas, too much gas, intermittent spark, dirty furl system, bad valve setting, low compression, broken valve spring it goes on and on. You have to systematically check all the functions to find the problem. I was fooled on mine until I got out the test set and started looking. John

Posted: Tue Dec 31, 2013 5:17 pm
by joebuck
Thanks for advise guys. I do know 100 % my jeep was running like a top until the little bath. After I got out of flooded road, the engine took a tweat in running . Basically when I floor it , it never rev up fully. Sounds like it runs rich

Posted: Tue Dec 31, 2013 8:25 pm
by wesk
Then start troubleshooting in TM 9-8012 page 75, item f. Engine does not develop full power.

Posted: Tue Dec 31, 2013 11:09 pm
by joebuck
Thanks for advise guys. I do know 100 % my jeep was running like a top until the little bath. After I got out of flooded road, the engine took a tweat in running . Basically when I floor it , it never rev up fully. Sounds like it runs rich

Posted: Mon Jan 06, 2014 8:43 am
by joebuck
Heres what i found.....#2 plug wire not showing a good spark. Switched plug wires to rule out bad wire and now decided it was distributor. tried to clean with emory the sooted post with no avail.. So ordered a new 24 v distributor cap

Posted: Mon Jan 06, 2014 11:36 am
by wesk
Be sure the cap you ordered is not an imported cap. They are notorious for giving you grief brand new out of the box!

Posted: Mon Jan 06, 2014 11:43 am
by joebuck
oh lord.........heres what i bought... did i screw up?

http://www.ebay.com/itm/17244-03-24-Vol ... f8&vxp=mtr