1971 Sidewinder jet boat

[jetboatjill]

Restored 1971 Sidewinder jet boat, used original motor mounts, rebuilt engine, now transom will not lift, will not launch, will not float, takes in water due to exhaust being below water line? How can we lift the transom? We did NOT add any weight from the original boat just completely rebuilt engine?

[jetboatjill]

PLEASE HELP! Spent too much time & money for boat not to float. Everything works perfect, boat just will not launch, float, lift off trailer.

[cyclops]

Did the boat float off the trailer with the engine in it for you, before you rebuilt the engine?

[jetboatjill]

We bought the boat from these people who had the boat sitting out in the weather for 3 + years. NO, the boat did NOT even have an engine in it that worked when we bought it, however, we did use the original 455 Olds engine block that was in it - took block & got it bored out, rebuilt engine - all new parts. As far as we know, the boat has not been off the trailer for the past 5 - 6 years that we know of. The back of the boat (stern) appears to be too heavy to lift the boat - the back end will not float. Water rushes in the exhaust when we try to launch the boat because the exhaust is BELOW the water line when we try to launch the boat? We've not added any weight, just rebuilt the engine that was in the boat. So wonder what makes the back of the boat so heavy that it won't lift? The back end of the boat needs about 12 inches in order for it to float so water will not rush in the exhaust. We don't know what to do? The engine has all new parts, everything works perfect except that we can't get the rear end to lift / float. We put a racing cam, racing pistons, and a high performance carb on the engine, but that would not add too much weight in order to lift the back end of the boat? So we are at a loss as to what to try or do?

[cyclops]

I have 2 thoughts. The 455 is NOT the right weight engine. OR more likely, the boat has soaked up water thru openings that let in water from a, sinking or rain . Engine too heavy. Boat too heavy. Both are too heavy. Pull the plugs out of all cylinders and spin the engine to get most of the water out. 5-10 sec. max. as you have little or no oil in the cylinder walls. You can scratch the compression out of them. Get and DO A FOGGER OIL SPRAY JOB into each cylinder. Again crank for 5-10 sec. stop. Change oil and filter. New filter & oil. New plugs. Start it on the trailer with the straps still holding it, while it is on the boat ramp with the pipes out of water. MAKE damm sure the cooling water inlet is in the water. Start it and run it for 15 to 30 seconds. DO NOT go above a fast - 1000 rpm idle. STOP. Change oil & filter again. Pray you are very lucky. IF the engine is the right one it ran with. Then the boat is water soaked completly under the floors. Check around to make sure that boat is supposed to carry that heavy of a engine. Check back and good luck.

[jetboatjill]

Cyclops, you are a dear! THANK YOU for your reply. We plan to go to the lake next weekend and will plan to try your ideas! We're beginning to think that the engine is too heavy for the boat, however, it is the original block that came with the boat. We heard from a marine engineer and he told us that since the boat has not sat out in rain, etc for the past 3 years, he does not think the boat has gained weight from soaked stringers.......so........unfortunatly, we fear the engine is too heavy for the boat. We gutted the boat and restored it from a bare hull. So, we wonder why since we used the engine block that came with the boat? You don't suppose they tried to use the engine and found it was too heavy and neglected to tell us? THANKS again for your help! We certainly will take your advice! Have a GREAT weekend! We'll let you know how things go next weekend! THANKS again! jetboatjill & johnnyjetboat

[cyclops]

If you can. Find a similar size and shape boat. Note how level it sits in the water.Forget all that stuff. Do a web search of jetpump manufacturers. Call several of them and ask if the engine is too heavy or if the pipes are too low or if the hull has soaked up too much water from being outside. FLASH!! Take your boat on the trailer to a set of accurate truck weighing scales and get the weight of it alone on the scales. UNHITCH IT. THEN call the jetpumps Manufacturers. They will know where the problem lies.-------------------------------------You did remove all the tie down straps???? Wish that was it. It easyly could be a dummy engine to make their sale quicker. Let us know how you do.---------------------Have you ever crawled under the boat and checked every inch of the bottom and around the pump housing for all of the following. cracks, holes, patches or a coat of paint to hide all of those problems. When you pull the boat out on a ramp. Does water drain out for more than 10 seconds?

[cyclops]

I did a web search of --sidewinder jetboats. 17 & 18'. They came up with big blocks in them. I now lean to the boat being water logged. Hope you prove me wrong.--------------------------------------------------------- Is there any way you can check between the floor and the space below it? Any place? Where the fuel hose goes to the tank? If so, smell there, wet odor? Gas odor? ---------------------------------------------Did water ever show up on the floor or anywhere when you tried to launch it?--------Is there a drain plug anywhere?

[jetboatjill]

Cyclops - you're AWESOME!!!! Weighing the boat is a great idea!!!! We completely gutted the boat and restroed it from scratch. It has a new floor and new stringers and new foam. The boat has been dry for 3 years since we've had it. Yes, there is a drain plug that goes in the side of the jet pump. We DID have the drain plug IN the drain plug hole - a NEW drain plug at that! Where the exahust pipes come OUT of the back of the boat, there are rubber flaps on the very end of each exhaust pipe that flaps in the breeze. We understood that when the water rushes against the rubber flap, it is supposed to close that rubber flap? Is there supposed to be an additional rubbber gasket somewhere that's supposed to keep the water out of the exhaust pipes when launching the boat? The rear end of the boat (stern) did not lift, float off the trailer. It's as if either the rear end is too heavy OR for some reason, there seems to be no bouyancy to the back of the boat. - OK, NO offense to men, BUT, as you can tell, I am the one seeking advise and help where as my husband is NOT seeking help! He says he's always had to rely on himself and do everything for himself all his life where I seek advise and help when needed. I suggested to him that we go to a marina OR have our friend (who also has a boat) watch & help us launch the boat.....BUT.......he is being very stubborn about this!!!! I feel we need someone here who can visibly see & watch us launch the boat who is trained in that field of work. Cyclops, I wish you were here to help!!! You have been so patient and so kind to help us. It seems to be such a mystery? The rear end of the boat should lift, float off the trailer. How far into the water should the trailer be? We do not have a 4X4, we only have a Dodge Dakota 2 wheel drive p/u. When we tried launching the boat the first time, the tail pipe of our truck was under water and the boat was still not half way in the water on the trailer, but, still, when the rear end was in the water, it still should have lifted off the trailer and started to float at least? Right? Years and years ago I had an old ski boat w/ an I/O and it always lifted off the back end of the trailer. I can't begin to THANK YOU enough for all your help and time you've spent trying to help us - wish you were here!!!! MY thoughts: I wonder if the engine is too heavy, the ramp was too steep and we don't have a tall enough truck, OR the rubber gaskets are rotted or missing from the exhaust pipes? It seems to be that there should be some sort of mechanism that should keep the water from flowing in the exhaust pipes when you're launching the boat, UNLESS the rear end is not supposed to be so low? Oh what FUN this is?!?!?!!?? Enjoy your Sunday and have a nice week!!! THANKS again for all your help in trying to help us solve this mystery!!!!!! MY thoughts: I'll give up when a marine mechanic / technician or professional boat desiger tells me the boat won't float!!! Until that time, I will not give up trying!!!! jetboatjill

[cyclops]

Do a web search of----sidewinder jet boats----- then click on the site of --boat types--- the scroll down to--- sidewinder---- there are several with the engine sizes in them. Let me know if any are your size and engine. Critical part is the depth of the hull under the engine.-------------I think you need contact on the web sites with Sidewinders. Post back if any look good. ------------------- I did not know you did a floor pull up and replacement. I am back to a heavy engine in it. Not the end of the boat engine combo. Could be very DOABLE if weight is shifted to bow area on the center line of hull. We in NJ put Chevy 350's in our swim short's. A real float test is to buy a pair of Plumbers rubber test plugs at a plumbing supply place. Measure the I. D. of the stern pipes and get the plugs to fit them. Plug the pipes- no leak into the engine- finger tighten the wing nuts. try to float the boat UP ONLY. Leave the safety line on and back the winch cable loose 4" to 6"max. Test is to see if the boat can BARELY and SAFELY float. If yes, great, only 50 to 100# in the bow. If it gets close to looking too iffy. Have someone loosen more winch slack, lock the winch. Someone climb on the bow. It should pull the bow down way too much, hopefully. -------------------------The idea and goal of all this cautious body movement is to keep it reasonablely level while adding a driver and passenger slowly towards the seats.-----REMEMBER THIS. BOW person is first on - LAST OFF.-----------------------------------------------------------There is nothing wrong with adding BOW weight IF it is epoxied on a 3/4" piece of--- Marine plywood AA or AC-- Which is also sealed and epoxied to the keel runner or floor area in the bow. I think 100# in the bow will make the boat sprain your necks with ease. Carefull float first with the bow person. HIT IT. WAHOO!!!------------------DO NOT LET THE BOW PERSON OFF till the boat is resting ON THE TRAILER IN THE WATER.

[cyclops]

Once you balance the boat with passengers you can move them around to see how touchy the boat is to weight shifting. Weigh the bow person and put a piece of DUCT TAPE on the floor where the boat looks right from a side veiw with driver alone and maximum people? 4? You will find you only need to add enough bow weight to float the empty boat at the right racy angle. Hopefully more seated people pull the bow down. --------------------------------------------After you get some balancing confidence, fill the fuel tank and retest. Do the same empty if possible. All this juggling is done over and over till there is NO DOUBT on how to balance the boat SAFELY and so it always has a slight BOW UP look to it with 0 or maximum people in it. The big engine may limit # of people by -1. Post back on the float tests. After we get it floating we will take care of the prop losing it's grip on a full throttle acceleration. Fun boat is almost ready.

[jetboatjill]

Cyclops, how can I send you photos of our boat? Esp the back end where the exahust pipes are AND I have a couple of engine pics I can send to you. You truly amaze me w/ your expertise! You are so patient and kind to help us.

[jetboatjill]

Cyclops, I am a school teacher so I will not be on the computer until evening during the week. We plan to go to the lake next weekend to "experiment". You have given us several great ideas to try out. THANKS again!!! Take care & have a nice day.

[cyclops]

Do the web search I asked, and post back.

[jetboatjill]

I did Yahoo search, Google search and Ask Jeeves search and can NOT find the web search you're talking about. :-(
Tell me which web search to use..........PLEASE!!!! :-)