Trojan Boat Forum

Hey guys been a couple months since my last post but figured I'd update everyone and ask some more questions. First I'll start by saying I bought a 1973 trojan f31 and everything ran and worked great when I inspected it in person. I currently have it docked in Norfolk, VA and haven't had the chance to transport it to Savannah yet. Me and a buddy decided to load up the 4 cylinder car this last weekend and try her out in the chesapeake bay for first time but hit a ton of snags.

To start with we got there and one engine wouldn't fire so we jumped the other engine off and let it idle while we diagnosed the no start. While the engine was idling we heard the belts start squealing horribly and noticed the raw water pump was now leaking. We shut it off and found out that the other engine wasn't getting fuel. I ran to the local auto parts and grabbed a cheap mechanical fuel pump but that didn't help at all. I then decided to blow into the fuel lines to see if they were maybe clogged but we could here the bubbling in the tank. I currently have the marina techs diagnosing the no fuel problem and locating a raw water pump. I really hope that tank was just out of gas. I did try to remove a plug in the top of the tank to see but it was stuck good.

I wanted to also use this post to see if anyone knows if it's possible to put maybe four 60 gal tanks under the deck to increase the cruise range? We are wanting to get into some part time tuna fishing and trolling for tuna all day can really suck up some petrol. Also is there a direct swap transmission available that maybe has 2 speeds instead of 1?

I now offer a little friendly advice to any new twin inboard owners. Don't try to leave the dock with one engine lmfao. Me and my buddy looked like 2 little fishies strung out on a trot line trying to get that heavy boat back in the slip.

CrunchyBacon wrote:I then decided to blow into the fuel lines to see if they were maybe clogged but we could here the bubbling in the tank

there should be an antisiphon valve on the fuel line at the tank so if you blew air through the gas line and heard air bubbles in the tank then the valve is bad. its basically a check valve with a spring that keeps it shut and the suction of the fuel pump opens it, so you should have felt resistance blowing back wards, not getting gas at the engine could be that the fuel that was in the line has been sucked back (bad valve) in to the tank and you would have to reprime the whole fuel line when you try to restart the engine. there could be a hole in the fuel line allowing air in also, so depending on how long you tried to start it with the engine you may have never pulled enough fuel through the line to the engine of course being out of gas is an issue. also is there a crossover selector valve that would let you select the other tank for fuel? fuel manifold?

Sounds like there is no check valve at the tank . Most likely not the problem but also needs to be addressed for safety as does auto fuel pump . I believe you can increase the fuel capacity , measuring is the way to figure it out . You would be better off replacing the tanks due to age (assuming oem) with larger ones . See what the marina techs say about the issue

2 speed trans ? I know of none for you application . Not sure how far you have to go for tuna down your way , but the F31 is not really a off shore boat . You would rally have to pick your days carefully .

Is the Boat at Cobbs in little creek ? Looks like it from the photo

@ prowlerfish yes it's at cobbs lolz. Good eye. I hear that alot about the f31's not being true offshore boats. Why is this? They are huge and heavy!!! 31ft long 11'9" wide?

Also as far as safety goes I'm building a list of stuff not working. So far we have the fire suppression inop, the fuel vapors blower inop, fuel check valves, and incorrect fuel pumps.

As for the no start on the starboard engine I'm letting the marina diagnose that. The port side engine just needs a weird looking 4 port raw water pump. I tried googling it but am having a hard time finding an exact match. Does anyone know what one I need for a 1973 trojan f31 with 318's? Thanks

Do a google search for Sherwood D55 or D60. Careful though, the port sizes are different between the two. If you have the old one you can rebuild it for a lot cheaper than ordering a new one.

I'm out of the water at Cobb's now. Hope to be back in the water in a week though.

The problem is the old one is on the boat. And it's 8 hrs away. Mine looked like it had 2 small ports coming out of the bottom and then 2 larger ports on either side. I can't be certain. But I was just hoping maybe someone had an exact model number.

The port on the bottom should match the size of the corresponding port on the top as they share the same impeller.

I'm headed down to the Cobbs tonight after work if you want me to take a look at it.

Can you call me at 912 536 9678. I'll give you all the info. That would be spectacular.

I'll call you when I get there. Probably around 4:00 or so.

Sounds good. Thank you so much. I should have thought ahead and brought them back with me.

I went ahead and let them know you were coming. You should be ok.