Fuel Tank

Mike.Deye · Post by **Mike.Deye** » Wed Feb 17, 2016 5:03 am

I am sure there is something on the forum about fuel tank replacement. But, I could not find so I apologize if this is a repeat question. I am going to begin shortly to make a new fuel tank for my Bertram 33 sportfish. I have looked for prints but have not found anything yet. Does anyone have a print for a Bertram 33 sportfish fuel tank ? That would be very helpful. Thank you, Mike

IRGuy · Post by **IRGuy** » Wed Feb 17, 2016 7:27 am

Mike.. I personally have been able to avoid the nasty ethanol/fuel tank fiasco that our wonderful federal government has foisted upon those of us who have gas engines, since I have diesels, but yes.. there have been many posts on this subject here since the ethanol problem first arose, and several of us have replaced our gas tanks. I am sure you will soon find several more knowledgeable responses to your post, so standby. As a warning, I believe it is true that there are more than one tank design as things evolved over the years, so I would think you would find the best info from someone who had the same model and year as your particular boat. Seeing that you are a new member here I would like to be the first "regular" here to welcome you to the best boating website on the net. There is almost no issue with our boats that hasn't been addressed by someone else previously, so feel free to ask anything. The hands on knowledge available here is not to be found anywhere else, and everyone shares their thoughts, experiences and comments freely. Tell us about your boat, and welcome aboard!

lobsta1 · Post by **lobsta1** » Wed Feb 17, 2016 9:24 am

Mike,.........WELCOME Rick Schaffer & I replaced our tanks at the same time. I honestly think you should pull the tank first to get actual dimensions. Then cut a sheet of plywood to the shape of the tank. Put it in place & slide it fore-n-aft to check for any obstructions. On Rick's boat we found we had to raise the bottom a little as the wings would hit the pvc pipe chase. Here is a thread Rick's replacement. Al http://www.bertram33.com/forum/topic.asp?TOPIC_ID=883

Rick · Post by **Rick** » Wed Feb 17, 2016 9:51 am

Hey Mike, welcome aboard. Take it step by step and definitely take your tank out for measurements first. I think you'll be surprised how quick you'll have it out of there. Keep calm and cut on ! Rick Ticket 85 SF Merc 454 MPI's Falmouth, MA

Mike.Deye · Post by **Mike.Deye** » Thu Feb 18, 2016 6:58 pm

Thank you guys ! Great information and this is certainly very helpful so far. We are going to start this as soon as the weather breaks up here. I have had my boat since 07 and it was repowered with Mercruiser 8.1 very shortly before I purchased it. Never any problems. The last few years, one engine will act as its starved for fuel. What is the most frustrating is that next the other will do the same ! They will run all day long below 1500 rpm normally. Its only under load and at higher speeds. I have replaced all the fuel lines, water separator never have shown water in it either. got into fuel tank and reach hand inside and pulled out several buckets of delaminated fiberglass. Fuel is a dark brown color too. It has to be issues with engine failure in my eyes. Regardless, I know the tank has to be replaced anyway. Its now time! Again, thank you for the help ! I really appreciate the response and will document for others future use.

Keith · Post by **Keith** » Fri Feb 19, 2016 2:27 am

Mike those engines are known to have fuel pump issues, I had to replace mine and I have a new tank. they are raw water cooled and get clogged with salt, at low rpms not enough water runs through them to cool the fuel for the fuel injectors. I bet after they stall you have to wait a little bit before they start again...

Mike.Deye · Post by **Mike.Deye** » Fri Feb 19, 2016 4:11 am

You are exactly correct. If I wait for awhile, they will act normally. I normally only would use the boat for short trips that were less than thirty minutes. Usually always worked fine. Then a few longer runs that were over thirty minutes the problems would reappear.

Mike.Deye · Post by **Mike.Deye** » Fri Feb 19, 2016 4:49 am

One more question. I have found some other threads after posting this one. But, one thing that I cannot find is what thickness of material did you make your new tanks of ?

Rick · Post by **Rick** » Fri Feb 19, 2016 1:24 pm

Mike, I have the 7.4 MPI's and can tell you that Keith is correct...they had some problems with fuel pumps but have been pretty much resolved. You can easily test it by purchasing a fuel pressure guage at Auto Zone or any auto parts store. It will screw directly into the fuel system. You'll find a valve on top of your engine that looks like a tire pressure valve on your car. Unscrew the cap, screw in the guage and start 'em, up. My engines need a steady a 40 PSI of fuel pressure at all times. Measure that at all RPM's and see what's happening. Now I told you that, so I can tell you this. I have a feeling it's not your pressure, but probably your fuel injectors. The good news is that you can have fuel injectors cleaned and they will run like new. It made a HUGE difference in my engines. Flagship Marine in FL will clean them for $50/injector and they'll Fed-X 'em back the next day. I used a place in Bow, NH that did them for $25/injector...think they're called "Diesel Fuel Injectors".....but they do gas too and did an amazing job with mine. FYI - dirty injectors could mean something is going on with your tank. So if your fuel pressure is good, that's where you'll probably have to go and they're not bad at all to pull from the engines. I can have all eight injectors out within an hour. Hope that helps.... Rick Ticket 85 SF Merc 454 MPI's Falmouth, MA

lobsta1 · Post by **lobsta1** » Fri Feb 19, 2016 3:12 pm

Mike, Here is what I found after cutting my tank open. What year is your SF? If a similar age you may be facing the same thing. Keep in mind, Rick & I replaced our tanks in the fall of 2006, so you tank is now another 9 years older than when I did my 1978. Al http://www.bertram33.com/forum/topic.as ... ee,grounds

greysole · Post by **greysole** » Sun Feb 21, 2016 7:52 am

Hi Mike, What year is your sport fish? Mine is an 86 & we replaced the tank last year. Made out of 3/16 Aluminum 5052. Cost @ 4K. How long have you had ethanol in your area?

Keith · Post by **Keith** » Mon Feb 22, 2016 3:07 am

Mike I had made my tank made out of stainless

lobsta1 · Post by **lobsta1** » Mon Feb 22, 2016 9:48 am

Mike, I think Keith has nailed the immediate cause of your problem. Secondary could be what Rick said about the injectors & that could be caused by the tank. Al P.S. Like Gerard asked; what year is your SF?

Mike_Lenz · Post by **Mike_Lenz** » Wed Feb 24, 2016 3:57 pm

Mike, Check out AUS Injectors, I represent this company and we offer Marine Injectors. I put a set in my boat and it ran great. In most cases they are easy to install. Below is the website. http://www.ausinjector.com/marine-injectors/ Good luck, Mike L.

Mike.Deye · Post by **Mike.Deye** » Sun Feb 28, 2016 5:37 pm

Sorry for my delay, but Thank you ! This is a wonderful forum with some very good information. I like the ideas of cleaning the injectors and I can see that happening. Me and some buddies just pulled the tank out this weekend. We didn't get to see it inside yet as everything is still pretty much assembled. And Gerald, I did find a guy to make it out of same material for 3800 plus maybe some extra depending on what he gets into with baffles. I think the guy was right in line on pricing. My sport fish is 1988. I have owned since 2007 and it was repowered in 2005 I believe. Previous owner repowered with 8.1. I have seen inside of tank once and it was right when running poorly. I had dug out a 5 gal. bucket full of delaminating fiberglass. Not sure of where any ethanol fuel but from what I hear, it winds up on gas docks even when they say its not. With all of your comments and suggestions, I think that this problem is coming together for me ! I live in Michigan so we had a nice weekend to get ahead of schedule this weekend. but, still a few months from experimenting with this. AGAIN, THANK YOU TO ALL !