Diesle can't purge to restart after repair.

[blake711]

Hello all first post. Great site you have here. I got a Perkins 3 cylinder with a cav fuel pump on it. Here is an image I found online that looks like it http://www.realdiesel.com/images/dpapump_030.jpg The plate on the side the gasket was leaking very badly so I replaced the gasekt along with the fuel filter that apeared to be 20 years old. I bleed the system through the fuel filter by cracking the screw on teh top. That side of the engine has a small auxillary pump that had a hand lever on it. I used that to pump the filter full then went to the other side where the main pump and injectors are. I cracked open the one injector I could reach and I only get a small trickle of fuel a drop every now and then. I cracked open the lines on at the pump and get a good solid stream.

After searching online I saw someone say this pump has a bleeder valve. I took a chance and opened the screw that is on the main body just left of the plate that needed to have the gasket replaced and directly above the seriel tag. It had tons of air in it.. Finally purged that and decided to try that top screw that is above the one I bleed. These two screws look Identical and the one on the top is just strait above the first one I did bleed. Currently I am down at the moment as the old battery needed a rest and I got the charger on it. I know I am making progress as I got a ton of air out through that main body screw that I hope is a bleeder. Anyway I need to know is teh identical screw above it a bleeder also? IS it safe to crack it open and try to purge air from there also? Lastly after I do or don't do that any pointers on how to get a stready stream at my injector? Everything looks ok to the pump. It fired for me one time but I think that was after I Realised the pump kill switch wasn't out.

Thats one other issue. The cable is broke so I have to manually move that kill stop. I belive if you are looking at the pump it should move to the left. But at this point I have been screwing with this thing for 2 hours and question everything now. Sorry about the long winded post your input is appricated.

Blake

 

[Farmwithjunk]

I'll take a look at the fuel shut-off on my Perkins AD152-3 (MF 150) tomorrow to see what direction "off" is. Can't remember off hand.

Bleed as much as you can BEFORE the primary pump.

Bleed lines from primary to filters.

Bleed filter assembly.

THEN start with the injector pump.

You described the upper chamber and lower chamber bleed screws on the main pump. Bleed lower completely (until steady flow of fuel with no air bubbles comes out) shut that screw and repeat with upper chamber screw.

That one injector you can reach SHOULD vent enough air to get the engine to fire. You need a good flow from the line just before the injector. NO air bubbles. You can loosen the lines AT THE INJECTOR PUMP to vent some air. Be carefull. Lay a rag over the connections you have loose. High pressure fuel stream can do serious harm.

It may take REPEATED attempts. Also, that primary pump can (and does) go bad. There is a kit available from MF (AGCO) to rebuild it. Sometimes it'll go bad, letting fuel leak into the engine (crankcase) Other times it will leak externally. And if you're lucky (????) like I was, it just quits PUMPING. It will pump SOME when manually activated, but won't do squat when the motor is TRYING to start. It will suck air from outside and just recharge air into the fuel system.

Keep trying. It's not always easy, but after ENOUGH bleeding air, it will run again.

 

[Ryan03]

hello blake, sometimes it can be vert difficult to purge air from a diesel fuel system, however, it sounds like you are on the right track. one method that I often use when I get a stuborn one is to first try to bleed the fuel system in order from the filter bleeder to the filter discharge line at inj. pump, from there, if the pump has a return line to the tank off inj. pump, I will bleed that next, if not , I will go to bleeder screw on pump and bleed there. next, I will crack all accessible injector lines loose at inj. pump till I get good squirts coming out of them as I crank the engine. As you crank the engine, pay close attention to the exhaust to see if you are getting any smoke, normaly it will be grayish blue, if you have smoke, you are probably getting close. I should probably ad that once you begin to bleed fuel injector lines that it is neccecary to crank engine over to move fuel rather than pump hand primer, you probably knew that already , but just thought I had better throw that in , just in case. next, move on to fuel lines at injectors, if you have them, a crows foot line wrench set normaly works real good for accessing most injector lines and can be had at most Napa stores for around 30 bucks. If you still cannot get it bled, you may have a air leak somewhere, go back and check your fuel filter for missing or improperly seated o rings and seals. One thing I normaly do when changing fuel filter is to put a new coffee filter over top of fuel filter and pour diesel fuel through coffe filter into new fuel filter until it is full of fuel and then carefuly install it and prime system. this will save you lots of bleeding. Good luck and may the force be with you!!!!

 

[dieselsmoke1]

The fuel shutoff will be pulled to actuate. Off will be the direction the cable would pull if it were connected.

What is the engine powering? I ask cause if it's a tractor, better to pull start a stubborn airlock than toast your starter. Manually pump all full to the injection pump inlet, slightly crack the pump bleeders and an injector, hook up a chain and let her rip.

 

[blake711]

Thank for all the info so far guys. First I will answer the last question its a tractor a Massy 230 with perkins 3 cyliner.

Contiuation of Trouble shooting. Well I went out again after dinner the batter had some time to charge a little only had a few minutes of light left. Anyway I cracked open the bottom chamber bleeder on the pump and it was solid no air. Then I Tryed the top bleeder on the Upper chamber as Farmwithjunk called it and I never saw a drop of fuel. I cracked open the line at the injector and it has a small amount. I cracked open two lines hanging off the end of the pump that go to the injectors and both of them had fuel coming out. Anyway that was all the light and battery I had left. I got teh charger on it and will let it sit overnight. Give her another shot in the morning. I will ryans suggestions a shot as far as bleeding the lines to and from the pump from the filter as they are on each end of the pump also there is a return line to the tank I belive that I will check.

Any input on why I Am not getting anything in the upper chamber is appricated. When I tryed to purge the upper chamber I made sure to close all other connections so it couldn't try and syphon air. Anyway the upper chamber has me stumped currently.

Blake

 

[gemini5362]

This might not be the best method but when I changed the filter on my Massey Ferguson 65 ( or when worse yet I did not watch my fuel level and ran out of diesel) I would pump with the hand pump until I got diesel coming out of the two bleeders on the injector pump. I would close them then I would open one of the injector lines. I then took my pickup and a chain and had my son pull the tractor while I was driveing it in second gear high. after about a 1/4 of a mile or so i would see diesel coming out of that injector I would stop and close it and open another one. by the time I got to the third injector bled (usually after about a mile or so of towing) the engine would fire up and I would then just finish bleeding it while the engine was running. This saved a lot of wear and tear on my starter and seemed to work pretty well the times I did it

 

[Farmwithjunk]

Thank for all the info so far guys. First I will answer the last question its a tractor a Massy 230 with perkins 3 cyliner.

Contiuation of Trouble shooting. Well I went out again after dinner the batter had some time to charge a little only had a few minutes of light left. Anyway I cracked open the bottom chamber bleeder on the pump and it was solid no air. Then I Tryed the top bleeder on the Upper chamber as Farmwithjunk called it and I never saw a drop of fuel. I cracked open the line at the injector and it has a small amount. I cracked open two lines hanging off the end of the pump that go to the injectors and both of them had fuel coming out. Anyway that was all the light and battery I had left. I got teh charger on it and will let it sit overnight. Give her another shot in the morning. I will ryans suggestions a shot as far as bleeding the lines to and from the pump from the filter as they are on each end of the pump also there is a return line to the tank I belive that I will check.

Any input on why I Am not getting anything in the upper chamber is appricated. When I tryed to purge the upper chamber I made sure to close all other connections so it couldn't try and syphon air. Anyway the upper chamber has me stumped currently.

Blake

With all your efforts so far, and no signs of fuel at the upper bleed screw, you're drawing air from some point. It MAY still be air in the filter or a line prior to the injector pump, but may be a loose connection somewhere. Injector pump will pull air easier than fuel. As soon as it draws air, the pump quits drawing anything. You need to get a steady flow through that top bleed screw. On a few stubborn ones, I've completely removed that screw until flow starts (by hand priming at lift pump)

 

[blake711]

well it looked like I just needed a little time away from it. I put the charger on it last night got up this morning. Went out checked all my connections. They were tight. I went ahead and pulled the upper chamber screw and pumped the manual lever on the filter side after 15 or 20 pumps I went around saw fuel coming out. I bliped the starter a once to get solids stream from top purge screw. Tightened it down. Then cracked the main line open. Hit the starter for about 10 seconds and it wanted to start held it till about 15 seconds and it was running. I let air purge a bit tighened down the line and all is well in the land. I finsihed routine mainantece this morning and shes running like a top. I think a lot of it had to do with the battery being so low just didn't have enough ump to get it up to 500 rpms or better. This morning it fired right off. After I did some other stuff I started it twice today both times it fired right off like it always has.

Thanks to all those that posted you saved the day for me.
Blake

 

[RobJ]

My BIL's old MF 1080 had one of those pumps on it. Always having problems with bleeding and air. Worse was MF use of these little rubber washers. Not sure why they didn't use a standard banjo fitting with copper washers.

Glad you got it going. At least once bleed, his did work ok. But it was rebuilt twice in 5 years for other problems.