F-36 Transom Fuel Levers

Plan B · Post by **Plan B** » Sat Apr 18, 2009 1:16 am

My F36 has two levers just to either side of the sliding glass door just above the transom floor that state "open" or "close" and the lever can be pushed to either selection. What exactly do these levers do? I am guessing they switch between my two main saddle fuel tanks and my to rear spare tramsom fuel tanks? When "open" is selected what function is taking place, and when "closed" is selected what function is taking place?

Thanks,
Plan B

aaronbocknek · Post by **aaronbocknek** » Sat Apr 18, 2009 6:10 am

my 76 f-32 has the same set up. it is used to transfer fuel from saddle tanks to aft tanks and enable the use of all 4...... personally i only use my aft tanks since i do not (at least for now) plan on doing any 'long haul' cruising.
aaron

ready123 · Post by **ready123** » Sat Apr 18, 2009 11:33 am

aaronbocknek wrote:my 76 f-32 has the same set up. it is used to transfer fuel from saddle tanks to aft tanks and enable the use of all 4...... personally i only use my aft tanks since i do not (at least for now) plan on doing any 'long haul' cruising.
aaron

I only have aft tanks but have often thought if I had all 4 what would it be like to run using only the saddle tanks. Reducing the aft weight in that manner should change how she runs.

Has anyone tried this? Is my expectation that more lift at the aft end would be a positive... true or false? Increased fuel economy and speed per rpm? Effect on handling in a beam sea?
Have you tried to see the difference of this setup Aaron?
Can any other F32's with 4 tanks answer this?

aaronbocknek · Post by **aaronbocknek** » Sat Apr 18, 2009 1:45 pm

good question michael..... to be honest, the starboard exterior lever is really hard to move, and i am afraid if i muscle it too much, it might break. then i would not know if the flow valve is in the open or closed position. so, for now, i just use the aft tanks and use the trim tabs. when i purchased the boat, the broker told me the previous owner never even used the saddle tanks and i am not sure how much "schmutz" is in the bottom of those saddle tanks. personally, i would love to remove them for the wiggle room in the engine area. trying to change the outboard sparkplugs is going to be a huge challenge since there is very little room to work.
but thats just my opinion. oh, any information from starboard company and the h channels? i have yet to be able to schedule a meeting with midatlantic plastics.
aaron

Plan B · Post by **Plan B** » Sat Apr 18, 2009 2:45 pm

Thanks for the replies.

So, which set of fuel tanks are larger, the saddle tanks or the aft tanks? I am pretty sure the saddle tanks on my 1972 F36 are the larger fuel tanks.

Can I shut off the fuel supply from just the saddle tanks so I can burn off and use only the fuel in my aft tanks only? I am planning on taking the aft fuel tanks out of service due to concerns with some rust found on the outside of the aft fuel tanks, and want to first burn off the fuel in the aft tanks only if possible.

Plan B

prowlersfish · Post by **prowlersfish** » Sat Apr 18, 2009 8:52 pm

on the F36 the saddle tanks are 125 gal each and the stern tanks are 50 gal each total of 350 gal all F36 conv. came with the saddle tanks the rear (stern) tanks were xtra

wowzer52 · Post by **wowzer52** » Sun Apr 19, 2009 1:07 am

My F-32 has all four tanks, two 50 gal saddles and two 62 gal rears. The rears are the mains, the saddles are/were factory options. I ran saddles only all last summer. The boat handle terrible at most speeds. It was hard to find a sweet spot where it would track straight. At hull speed with the rear tanks empty and the saddles full the boat rode slightly bow down, very noticable, especially to those at the dock who were watching me cruise by, of whom always brought it to my attention. Even on a plane the boat did not track as well as some other boats I've had. Now I run the rear tanks only and the boat handles great, at all speeds, even at slow speeds in following seas. Totally different boat. I have thought about taking the saddle tanks out for better engine access but they are not hurting anything as they are but I would never even consider taking out the rear tanks. The boat handles better, planes and runs smoother with less trim tab and feels more settled in the water with the saddle tanks empty. If I'm planning a long trip I will fill all of the tanks and use the saddle tanks first, but now I under stand why Trojan made so many F-32s with rear tanks only.

prowlersfish · Post by **prowlersfish** » Sun Apr 19, 2009 5:20 am

My boat will do that at higher speeds fuel level makes no difference . but that due to the extra weight of the diesels . I was surprised the mains are the rears on the F32 , but given the way it handles it makes sense. I guess the side / saddle tank were a popular option on the f32 as the few I have seen all had them ( that I have been in the engine room to see ). about 1/2 of the f36s I seen had the rear tanks .

Dan Faith · Post by **Dan Faith** » Sun Apr 19, 2009 7:43 am

My F32 has the saddle tanks and the aft tanks. I have ran it with all full and used the aft tanks first then relied on the saddles as though they were the mains. For the last two years I have ran with the aft tanks emty with the idea of leaving the weight out of the stern. It has handled good but I will try running this rear with the saddles emty and use the aft tanks so I can compare the performance in this configuration. I'll report back the results once I'm in the water.

great post a lot of good information here

ready123 · Post by **ready123** » Sun Apr 19, 2009 9:38 am

So that is interesting... Dan Faith and Wowzer52 have opposite results. I think we need some more information to understand the difference???

So the next question is what props? Any chance Dan has 3 blades and wowzer52 has 4 blades... as the 4 blades would give more aft lift?
Do either have dinghys on the swim platform. How much water? Is holding tank in the rear?

I have a dinghy on swim platform adding about 700 lbs and 100 gals of water between my aft fuel tanks (62 gals ea), holding tank is under V berth, have used 3 and 4 blade props which is why I asked the question. I have felt at the start of a trip, all tanks full, I would like a little more lift at the aft end. The aft end is underwater to above the top of black striping. With no dinghy & 4 blades she runs fine... but Georgian Bay boating requires a dinghy.

Dan Faith · Post by **Dan Faith** » Tue Apr 21, 2009 9:41 am

One thing on WOWZER52's I noticed his saddles are the smaller tanks, mine are just the opposite rear tanks are 50's the saddles are 62's. Also I have CHY 360's 3 blade props I looked at a 75 that had 318's a lighter engine may have some impact on results. I do not have a dinghy on mine. Ready123 I'm considering moving to 4 blade props how did that impact your performance RPM's vs speed and fuel burn? What engines do you have?

ready123 · Post by **ready123** » Tue Apr 21, 2009 10:06 am

Dan Faith wrote:One thing on WOWZER52's I noticed his saddles are the smaller tanks, mine are just the opposite rear tanks are 50's the saddles are 62's. Also I have CHY 360's 3 blade props I looked at a 75 that had 318's a lighter engine may have some impact on results. I do not have a dinghy on mine. Ready123 I'm considering moving to 4 blade props how did that impact your performance RPM's vs speed and fuel burn? What engines do you have?

How did you get your tanks like that? Are you sure... wowzer52 has the Trojan factory layout.

I have 318's and I lost a little top end got lower to plane speed and the fuel economy seems better. I did not have the 3 blades on for long to really get full test results... and all my analysis is time, GPS distance, fuel refill based so has variablities within it... that a fuel measuring system could disprove my conclusions.

Low speed control & docking is better and it seems to handle the dinghy weight well..... though to be fair I did not have dinghy with 3 blades.

Maybe it is just my belief in the theory of 4 vs 3 blades that makes me happy!

wowzer52 · Post by **wowzer52** » Tue Apr 21, 2009 11:50 pm

351's, 15x15 three blade w/light cup.

Dan Faith · Post by **Dan Faith** » Mon Apr 27, 2009 1:00 pm

Went to the boat this week end and checked I was wrong the 62 gal are aft and the saddles are 50 gal. Once in the water I will try running with full in aft and saddles empty.

kevin babineau · Post by **kevin babineau** » Mon Apr 27, 2009 1:12 pm

my f36 has plastic tanks in the rear and big old metal saddles tanks...there r also holley electric fuel pumps one star one port....i assume that they are to prime the system...but any input would be great...are these pumps to run continuously? i have 454s with mechanical pumps