Fixed:... W50 not starting.

Down2TheC · **Posted:** 30 May 2012 00:29

Verified with the shop that they did an exact match for the thickness of the washers. And while the manual has the heatshields bump up, the shop assures me that they only provide heat dissipation, no compression. I'll go back tomorrow with a torque wrench. I winged it when assembling and tried for the 12 ft.lbs. by feel. Maybe I was being too gentle.

As for the water, I put a basin in the cockpit and let it suck what it needed. There was no water in the cylinder when I pulled an injector today so no harm no foul. But I'll hold off on that until I something's making heat.

And this time I checked and I have thick white vapor from the exhaust. So the pump and injectors are doing their job. Once I get compression enough to run WD40 I'll look to timing if she still won't start. I'm hoping the injectors just need a bigger torque to seal things off. Tomorrow makes 5 days staring at this thing... so I'm due.

Velera · **Joined:** 29 Dec 2006 09:38 **Posts:** 656

Seems like you are on the right track. Either timing or inadequate seal on washers. Those copper washers are crush washers and will not seal unless they collapse some when tightened. Very high pressure required for combustion.

On water in the engine from cranking: this will vary by engine and installation. In some installations where there is a long and high exhaust relative to the engine and water line, the starting mode will not be enough to clear the muffler and exhaust line--water will come out exhaust, but will also flow backwards between start attempts---requires actually running to provide enough air to prevent back flow. On my T37 the engine is rather low and the exhaust tube is long relative to water line. I have never had a problem with back flow, but I would see a potential for a problem if I cranked enough. Sounds like you are taking precautions to prevent this.

Down2TheC · **Posted:** 30 May 2012 12:21

Sure, now. After all the warnings. But it's never too late to start better procedures. Back in the day we'd just crank until she ran. The longest prior effort was after running the tank dry. This is the first time we're bleeding on the dry though. Same pressure needed to push a slug of water out the exhaust, and the run back after cranking stops should be the same amount flowing back to the muffler. So probably shouldn't be any different.

Of course the manual doesn't help since it has one bleed procedure in the maintenance section that doesn't address this, then in the overhaul section it has another bleed procedure that says cut off the intake if the engine doesn't start soon after bleeding injectors. Better safe than scuttled though so it's a new SOP for us.

jvoelxen · **Joined:** 21 Oct 2006 15:36 **Posts:** 268

Don't know if this helps but when I my engine is on the hard particularly while bleeding the fuel system I remove the belt from the raw water pump. You completely eliminate the concern about damaging the raw water pump and eliminate the back pressure making it slightly easier for the engine to fire.

You're probably aware of this also but it takes an incredible amount of cranking to fill the injection lines......probably 10-12 15 second cranks with the starter. Each time I have to do it I always have my doubts that it will ever start!!! But it always does.

Jim

Down2TheC · **Posted:** 30 May 2012 18:32

No joy... After torquing them down in the blind yesterday, I had them at 25 ftlbs. Still have lots of white vapor so I'm stumped. WD40 trick didn't work again today also so I'm probably going to say Uncle and call in the pro. (If they can get to me sometime this year.)

Down2TheC · **Posted:** 10 Jun 2012 07:27

So I've stumped the local diesel expert. He was only able to get it running on two cylinders after using ether (which I thought was verboten). He checked compression in the other two and it's fine. So he's thinking the pump was rebuilt wrong or those two injectors may be bad. Ball's back in my court. I twisted CCW in case it was just really bad timing, and with the pump in the center of it's available travel, I get some life out of one cyl while starting (I'm not touching ether). Today I'll push it more CCW and try. If no go, then it's time to take out #2 and #4 injectors to verify that they are spraying.

Sucks to be a special case. Also I'm completely guessing from pictures as to the proper pump setting. I scored a line, but the pump went through paint so my mark is long gone.

Velera · **Joined:** 29 Dec 2006 09:38 **Posts:** 656

I am with your expert. Something is not right with the pump or the injectors. I would take them back to the folks who rebuilt them. They should be able to test them both. You can test injectors out of the engine while cranking to see if there is a spray pattern of some kind. If not, will confirm your expert's diagnosis. Maybe he did that already.

Down2TheC · **Posted:** 12 Jun 2012 06:46

With it nearly fully CCW, it really wants to start but doesn't. So I did take one injector out and rig it sideways into a plastic bottle. It makes vapor. (And the return lines drip fuel all over the place... messy test.)
The wizard from the yard is coming this afternoon for one more shot to see what we can do. I just hate to get caught between him and the shop that did the rebuild.
"The pump isn't right but I can't tell you what's not right about it."

They'll say it bench tested fine, the yard will say it's not fine, and I'm stuck with no boat in June. Uncool.

Velera · **Joined:** 29 Dec 2006 09:38 **Posts:** 656

If it make vapor it seems like it must be the timing. That could be in the installation or in the pump---as you know. Really a bummer to be in your situation to be caught between the shop and the mechanic. Let us know how you come out. I am very curious.

Down2TheC · **Posted:** 20 Jun 2012 07:45

I'm now waiting for the yard to give me some time again with their diesel wizard.
I pulled all four injectors and mounted them upside down with the return line running into a zip lock and little bags rubberbanded to the injector tips. All four were blowing the bags about. Can't claim to know what they were shooting, but they were shooting. The bags jumped. I recorded and slowed down the tape and the order seems right.

So I'm back to a chugging start that has seemingly one piston firing. I get one puff of black each turn. The yard guy got it running on two cyls when I had no life in the starter... maybe he can get it running now that there's some life? We'll see.

Tartan37.com

Fixed:... W50 not starting.

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