| Author | Message | ||
| Joe Franklin (Franklinga)
Registered Member Username: Franklinga Post Number: 11 Registered: 1-2005 Posted From: 66.188.75.167 Rating: N/A |
I had the engine replaced in my MC9 (8V71) last year with a very good running engine from an MC7. I had a couple of local diesel mechanics to do the change over. Since the donor engine was originally coupled to a 4 speed transmission, it did require a fair amount of change over to install in my coach which of course has the Allison automatic. Due to time constraints, I only drove the coach locally a couple of times and then it sat in the driveway for about 8 months and I ran the engine only a couple of times for about 30 minutes. Got the coach out about a month ago and initially it ran exceptionally well. After about a mile the engine began to loose power as if it were running out of fuel. I pulled into a church parking lot and after a minute or so the engine shut down. I summoned a couple of diesel mechanics and about 5 hours later we finally got it running and I managed to get it home before the engine shut off again. I started the engine a couple days later (with some difficulty) and it didn't want to rev up. We suspected the fuel pump to be the culprit, so I ordered a new fuel pump from Williams Detroit. I was changing out the pump yesterday and I noticed the pump I took off the engine is a LH (left hand) rotation. The pump I bought is a RH rotation, which I thought should be the correct pump. Both pumps have the same casting number and appear to be identical except for the LH/RH rotation indication on the front of each pump. So, is the RH rotation the correct pump? If it is, how did the engine run with the LH fuel pump? | ||
| Luvrbus (Luvrbus)
Registered Member Username: Luvrbus Post Number: 905 Registered: 8-2006 Posted From: 74.32.84.228 Rating: N/A |
Joe, fuel pumps are left hand rotating regardless of the engine rotation they always turn to the left sec 2.2 page 1 of da book just in case you need a reference.RH is a high output fuel pump both will work for you good luck (Message edited by luvrbus on June 22, 2010) | ||
| John & Barb Tesser (Bigrigger)
Registered Member Username: Bigrigger Post Number: 424 Registered: 9-2007 Posted From: 96.42.5.35  Rating: N/A |
I had a similar problem on a semi one time and it turned out the interior of the fuel line had deteriorated and swelled until it cut the fuel supply enough the engine wouldn't run. Just another thing besides filters you could check. Good luck, John | ||
| marvin pack (Gomer)
Registered Member Username: Gomer Post Number: 941 Registered: 3-2007 Posted From: 71.55.3.249  Rating: |
Have you changed your fuel filters? A lot of times when you don't run them much the tank will accumalate algae and it will clog a filter slowly. When you let one set for a time always put stabilizer in it and that way you can be sure the fuel is ok, Just a thought Gomer | ||
| Joe Franklin (Franklinga)
Registered Member Username: Franklinga Post Number: 12 Registered: 1-2005 Posted From: 66.188.75.167 Rating: N/A |
Yep, we pulled both the primary and secondary fuel filter while we were in the church parking lot and both of them were full. I did add some fuel treatment a couple of times, but the fuel is over a year old. However, I've never changed the filter on the pressure side of the pump,so I'm going to change it as well. I'm also changing out all the fuel lines because they look to be quite old. I was going thru the archieves and I saw a couple of post where folks have pulled the pick-up tube from the fuel tank and cleaned the strainer on the end of the tube. I took a quick look at the fuel tank and it doesn't appear that you could easily pull the pick-up tube without grinding the weld to pull both tubes out. Does anyone know if you can pull the pick-up tube easily? I don't usually take the approach of "part swapping" to fix a problem, but the cost of these parts are not all that bad. I'm pretty sure I have a "fuel supply" problem, so this is a much less expensive approach than a tow or mechanic bill. Thanks guys for your help. | ||
| Luvrbus (Luvrbus)
Registered Member Username: Luvrbus Post Number: 906 Registered: 8-2006 Posted From: 74.32.84.228 Rating: N/A |
Joe, those pumps are bad about rounding the fork on the inside check and be sure the fork still has a square in it. good luck | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 1214 Registered: 10-2006 Posted From: 99.156.66.88  Rating: N/A |
I did add some fuel treatment a couple of times, but the fuel is over a year old. There are 2 types of bug killers . One drops then to the bottom of the tank, the other keeps them in suspension , for the filters to catch. Remove a primary and if its covered with small dark particles , that's Ashpalting , old fuel clumping , usually no problem for a bunch of filters. If it looks like snot on the filter that's the bug bodies . The bugs ONLY can live in water. Drain the tank , filter the fuel and stick it back in. 'If you removed all the water and snot , you have the problem solved. FF | ||
| Len Silva (Lsilva)
Registered Member Username: Lsilva Post Number: 375 Registered: 12-2000 Posted From: 72.187.35.208  Rating: N/A |
Add a fuel pressure gauge to the input of the secondary filter, it will tell you all you need to know to trouble shoot fuel problems. | ||
| les marston (Les_marston)
Registered Member Username: Les_marston Post Number: 85 Registered: 1-2010 Posted From: 68.151.225.213 Rating: N/A |
Fred ON the topic of fuel treatments. What would you suggest for fuel that could likely stay in a tank for up to 5 years? Les | ||
| Tim (Timkar)
Registered Member Username: Timkar Post Number: 141 Registered: 10-2004 Posted From: 64.141.73.7  Rating: N/A |
Used Biobor JF at work (stby gen diesel tanks)and have used it on my own equip as well http://www.conntect.com/fueladditives/biobor/ HTH....Tim | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 1216 Registered: 10-2006 Posted From: 99.168.83.142 Rating: N/A |
For 5 years only getting all the water out first will work. Sure a heavy dose of 2 kinds of bug killer will help , but if there is water , the tank is vented to air , the bugs will come. Why not simply drain the tank, and leave it EMPTY? Seal it best you can and it should be OK. Add a fuel pressure gauge to the input of the secondary filter, it will tell you all you need to know to trouble shoot fuel problems. I find the armored refrigeration glass better as you can see the fuel stream , and any bubbles in it. FF | ||
| Jim Wallin (Powderseeker01)
Registered Member Username: Powderseeker01 Post Number: 80 Registered: 10-2008 Posted From: 208.68.48.77  Rating: N/A |
The water source is generally condensation unless there is some sort of leak (unlikley?) In yachts and planes it is very useful to keep the tank full to minimize the opportunity for condensation. | ||
| john w. roan (Chessie4905)
Registered Member Username: Chessie4905 Post Number: 1916 Registered: 10-2003 Posted From: 71.58.71.157  Rating: N/A |
If you correctly wire a pressure sending unit with the proper switch point and connect to a light on the dash, you'll know when you have a supply problem. The Flxible I dismantled, had one hooked to it's filter tap. I'm going to install one on my coach. Use a good fuel gauge, preferably oil filled, but only for diagnostic purposes, unless you run a quality braided line and remote mount it. Engine vibration could cause a gauge failure and fuel leakage on a hot running engine going down the road. That's why they remote mount the oil pressure gauge. |
