Fuel Primers on a 3208

[SkippersList.com]

Umm ... What is normal when using the priming pump on the 3208?

With my starboard engine primer I can hear the fuel squirting back into the fuel tank via what I believe is the bypass or return line. Doesn't feel like there is any pressure being built up, but again I'm not sure if there should be any pressure build up making it harder to pump before you screw them back into the base. Easy to actuate and secure.

On the Port engine the primer gets hard after a few pumps but I can't hear any sounds in the fuel tank as I can in the starboard fuel tank. Kind of a pain to get the plunger back down to the base so it can be secured. Thus I wonder if the port fuel primer is suspect or maybe the bypass is clogged or shutoff somewhere.

When I asked the only person I know that seems to know diesels ... I was told the primer just puts the fuel in the system from the fuel tank to the injector pump, from there the injector pump draws the fuel in and distributes it to the injectors. (That would basically make the IP a fuel pump I guess.) So with that information it would seem that there is a problem on the port engine between the fuel tank and the primer, maybe a clog in the fuel bypass or something, but before I go thru the fuel lines from the tank back to the primer to determine where the blockage or malfunction is, I'm hoping someone may have some insight and constructive advice.

:smt100 :grin: :smt014 :huh: :smt021

On the flip side (Vacuum side) being from the fuel tank thru the filter to the primer ... I have to wonder if the clog could be in there as it would also restrict the plunger from drawing fuel in.

Possibilities:
Clogged filter, line or stuck bypass (if any) on the port engine
Malfunction post primer on the starboard engine. (seems unlikely given the info I've been given)

I have no problem doing the "Search & Determine"

Thanks in advance,

 

[tc410]

The primers on the 3126's in my previous boat had a small valve at the base of the primer plunger that had to be turned a quarter turn in order to allow the primer to pull fuel. If it wasn't turned open, the plunger would build pressure after a few strokes - which sounds like what is happening in your case. With the valve open, pumping for a few minutes would fill the secondary filter and then once full, fuel could be heard draining back into the tank via the return line. There was also a bleeder plug adjacent to the primer that could be removed during priming. Once fuel came out of that hole, it was indication that the filter was full. Replace the plug and prime a few more times until, again, you hear fuel draining back into the tank. assume it would be a similar setup on your CAT's.

 

[Boatingnut]

What is going on? Just a filter change? Some other issue?

 

[SkippersList.com]

What is going on? Just a filter change? Some other issue?

At this point its "Search and Determination" going through all the systems to determine what needs attention before I take the next step. (The ToDo List) Yes, an oil and a fuel filter change is in order before we splash her in August or September but I have a few issues I need or needed some insight on.

1. Fuel shutoff solenoid (needs to be replaced according to another post) Damn!
2. Fuel flow on the Port engine from the fuel tank to the filter to the fuel primer/filter to the IP back to the fuel tank. But it may be as simple as "I didn't unscrew the plunger" before I tried the primer. (fingers crossed)

Thanks to TC410 I believe I have a better understanding of what is or isn't happening ... hopefully it's just a dumb oversight on my behalf.

There are a few other issues on the port engine as well.

-The now Ex Marine we purchased the boat from and his wife split, They were living on the boat.
-The ex wife stayed on the boat and decided to move it off base to another marina,
-In the process the Port engine overheated and a water line burst,
-What I have been able to determine (what I believe happened from my observations) is that the raw water flow stopped.
- Both exhaust elbows and the turbo stand were / are baked ... when these parts started overheating the 1" water hose elbow that sits in front of the turbo stand got soft and ruptured and the engine was shutdown.
-After being towed back to the base marina, the ex wife then had a "friend" look at the engine and determine it HAD to be replaced,
-When the ex marine heard this he had a diesel mechanic on post look at the engine who said there was nothing wrong that he could determine other than the ruptured hose.
-The diesel mechanic added that the ex wife's friend had proceeded to cut several wires but he was able to reconnect them back temporarily to get the engine running again.
-Now sometime later, we are getting ready to service the engines and hopefully putt putt down the ditch from NC to FL to get her home. (new home)
-If no putt putt then transport. G

I believe either the raw water intake is clogged or the impeller let loose but won't be able to poke and prod again till June at the earliest ... and it's driving me nuts!!!! either way I'm going thru both of the raw water intakes and replacing both impellers as well as rodding out the heat exchangers before splashing.

Hopefully she'll be ready to putt putt after this.

The ToDo list continues. LOL