Perkins Fuel Injection Pump Timing Problem

[thatboatguy]

Some photos I took this morning.

The thing about it is, I was only giving a final check to what my pump rebuilder told me which was that so long as I didn't make any changes in regards to the rest of the engine timing, the pump would be timed right by those marks on the mounting flange and pump.

I'm a marine mechanic and I wouldn't hesitate to reseal a pump that I was certain was working properly. As it turns out, our pump was not producing enough output at cranking speed to reliably start our motor. You can't really test that with a drill in your garage. I knew the engine had low compression but I'm very glad I didn't just attribute the hard starting to that. I spent good money and manhours rebuilding our motor so I wanted to make sure the pump and injectors were "as new". So I sent them to the experts. The shop also checked our injectors and reported them as marginal but good. I had them rebuild them anyway and I spared out the old parts.

Some things you don't want to scrimp on in life; condoms, lawyers, and injector pumps.

If anyone needs a very reliable injector guy, I can highly recommend Jason at Advanced Diesel Systems

George

[dancamp009]

Thank you for your pictures and comment. I'm still not sure if you had your pump rebuilt or not and what was wrong with your IP that made you do what ever you did.
Had you bought a rebuilt pump as I did? Did you try it out and not like it? Did you remove it and send it out to have it inspected by another mechanic? If so, what exactly did the other mechanic find?
All these questions are important to resolving my problem. Hope you can tell me.
I wonder if your IP mechanic could comment on this forum and tell us whether or not the pump's main shaft loses tolerances as it gets old as a normal camshaft would round off and slowly lose it's ability to perform perfectly.
Thanks again
Thank you

[thatboatguy]

Jason, is very approachable and has answered all my questions before and after we did business.

I am in the process of rebuilding our Perkins 4-108. It had hard starting and low compression on two cylinders but ran OK otherwise. I decided to have the pump and injectors gone through by an injection expert. They found that the head had some discoloration but built the pump back anyway to see. When they tested it they found that it was not delivering sufficient fuel at cranking RPM's and asked me if we had had a hard starting problem. They replaced the head and the pump is now working up to new spec. They rebuilt the injectors at my request although they had been "marginal". My total bill for rebuilding 4 injectors and the pump including replacing the head was $738.40 including return UPS shipping. I view this as a bargain.

George

[sww914]

That is a bargain, I paid $900.00 for the same thing in Los Angeles. In Oregon they wanted $1100.00. An aftermarket rebuild kit is available from the UK for 25 Euros.

[thatboatguy]

Originally Posted by sww914

That is a bargain, I paid $900.00 for the same thing in Los Angeles. In Oregon they wanted $1100.00. An aftermarket rebuild kit is available from the UK for 25 Euros.

I completely agree, I'll use him again in the future for sure.

George

[thatboatguy]

BTW the pump kits are available on ebay, generally less than $30.00 in the U.S. And if you google around a bit you can find manuals for the CAV pumps and injectors in PDF format for free download.

George

[dancamp009]

Very interesting. I'm getting hard to start problems when cold also since installing this rebuilt IP as well as having to retard the IP to get it on time (no miss, good acceleration, decent low idle (8000 rpm). But I still have to crank it over quite a bit (aprox. twice for 10 secs ea.) while it's cold to get it going. It starts instantly when warmed up, so I'm not too worried about it anymore. My excess oil burning case was caused by excess oil in the crank case. I finally cleared that up with a proper oil change and installing a longer oil dipstick on right side (starboard) for accurate reference with exactly four quarts of 30 weight oil and filling up one new oil filter.
So it sounds like something called the "head" inside my IP might be a bit old and used up. I've just about exhausted my lousy one month return policy, and so I may be stuck with this IP, which isn't all that bad considering the complete hassle of removing it and reinstalling another one. Whew, a job I pray I will never have to do again.
What all this tells me is that if I ever have to do this again that I should either buy a new IP (good luck finding one) or have whatever rebuilt one I buy checked out by another rebuild mechanic before installing it.
Your IP mechanic may be the right fellow for this job. I haven't included my IP rebuild mechanic's name as first he was a real nice guy and helped me through out my installation problems. And second, this pump does work, it just had to be retarded a little. And because I may not really have a timing problem. After all, one mechanic said that as long as you can adjust it to run good, then you don't really have a problem. He said he has to change the timing on a lot on rebuilt IP installs. But who is he??? He is certainly not an IP mechanic, but he is a professional elder marine diesel mechanic, so I'll give him the benefit of my doubt.
So next time I'll have all rebuilt IP's checked out on a bench by another mech before installing.
Thanks to everybody for their comments here, I hope somebody besides me learned something. I know I did.

[avazquez]

What happens is that very few mechanics have the Perkins special tool to adjust the pump to exact specs. They use an alternate manual method which is specified in the Perkins manual. Then you have to manually rotate the pump to either advance or delay the injection timing. I had smoke upon start up after the rebuild and after some reseach found out. After rotating th IP the problem went away.

[phorvati]

George,
I can see the CAV marking, but I am wondering, is that DPA pump? That mounting flange is completely different from mine. My block is 4-108 but engine is westerbeke. I have a CAV DPA.
what is that "A mark" lined up with? is it the edge of locking circlip.

[thatboatguy]

The two types of distributor type pumps I've seen on these motors is the hydraulically governed ones and the mechanically governed. That's probably the difference you are seeing.

I'm anchored off Coopers Town at the moment just for an hour to get weather on wifi and then we are heading to Great Sale Cay, I'll try and post more on Saturday from Grand Bahama when we get connected again.

George

[DeepFrz]

Dan, it sounds more like you may have a leak in the fuel line somewhere allowing the fuel to drain back in the line. Have you checked it all very carefully? If it starts good and runs well when it is hot but not after sitting long enough to become cold it sounds more like the engine has to re-prime itself, rather than a timing problem.

[dancamp009]

Finally -- Problem Solved.
Two years later, after tossing this around in two separate posts on this forum alone (http://www.cruisersforum.com/forums/...lem-65846.html, http://www.cruisersforum.com/forums/...ent-94951.html) and a few other diesel forums on the internet, I've discovered why my new rebuilt Perkins 4-108 fuel injection pump had to be retarded 5/16" to even get my motor to start, and then with a lack of power while in gear.
The answer to my problem lied in the fact that the original IP shaft broke in two and this breakage forced me to buy another rebuilt pump from Armando in S. Calif. This month (two years later), I removed the IP and sent it back to Armando to have him check it out again along with the injectors. After running all the tests he sent it all back a perfect report. This time however, Armando suggested that I check out the timing gear that the IP is connected to, as this gear could have shifted out of position when the IP shaft broke.
Sure enough, I pulled the water pump">raw water pump off and the timing cover and discovered my raw water pump coupler was broken half off and the timing gear was out of align. After replacing the coupler and resetting the timing gear, all is fine. I now have the same RPM's I had originally (1900-2000 in gear) and the motor starts easily with the IP set exactly on line (no more 5/16" retarded) where it is supposed to be set. If I only would have known this before pulling the IP, I would have saved myself a lot of extra work and costs.
I will next install another heavy duty raw water filter in front of the raw water pump to prevent this same tragedy from happening again. We have a lot of kelp around here in the PNW.
Thanks for all your help on this one. If you ever need a good IP mechanic, I recommend Armando at RS marine Engine Service in San Pedro, California.

[tripak]

Confused as well on the line up on the circlip of the line to the flat end of the circlip if no mark. On 4206 engine which letter is it and assume this is lined up at TDC??