85 hp force wont start just backfires

[milkman]

milkman <br />First Mate <br />Member # 1776 <br />Rate Member <br /> posted August 25, 2001 06:02 PM <br />--------------------------------------------------------------------------------<br />just replaced head gasket on 85 85 hp force i need to know the ft lbs and the sequince .<br />also im having problems getting this motor to start all it does is backfire. it was in the shop for nine weeks and they gave up on it they could not even figure this motor out.<br />they say everything has check out ok sounds like its out of time but its not.its getting good fire on all cylinders.its getting fuel to all the carbs.any suggestion would help i am very new at this but iam somewhat mechicaly incline. they said compression was low on one of the cylinders but wasnt that bad for it not to at least start. i am stumped <br />--------------------------------------------------------------------------------<br />Posts: 7 | From: bellville IL | Registered: May 2001 | IP: Logged <br /> <br />12Footer <br />Captain <br />Member # 1024 <br />Member Rated:<br /> <br /> posted August 25, 2001 09:27 PM <br />--------------------------------------------------------------------------------<br />Torque is 18.8Ft lbs.<br />Now, how do I describe the sequence?<br /><br />There are two rows of nine bolts (18 in all).<br /><br />I will use letters for each row, "A" being the two top bolts,to "I", being on the bottom.<br />I will use L for left, and R for right.<br /><br />The number will be the sequence (2= second,5= fifth,and so on).<br /><br /><br />AL-17 AR-18 BL-13 BR-14 CL-9 CR-10<br /><br />DL-5 DR-6 EL-1 ER-2 FL-4 FR-3 GL-8<br /><br />GR-7 HL-12 HR-11 IL-16 IR-15<br /><br /><br />I hope you can follow that <br /><br />Try a shot of WD40 down the throat of each carb, and try to start it. If it sputters or runs for a brief while, it is a fuel delivery problem.<br /><br />--------------------<br /><br />I'm no expert, but I DID sleep in a hotel last night...I guess that's better than the dog house! <br /><br /><br />--------------------------------------------------------------------------------<br />Posts: 993 | From: Lehigh Acres, FL, USA | Registered: Mar 2001 | IP: Logged <br /> <br />milkman <br />First Mate <br />Member # 1776 <br />Rate Member <br /> posted August 26, 2001 07:04 AM <br />--------------------------------------------------------------------------------<br />thanks 12footer i understand your sequence perfectly.on the other matter about spraying wd-40 i have tried that serval times before with no luck. to me it sounds like something electrical.this motor is backfiring through the exhaust. just one loud pop everytime it tries to fire. could it be somthing electrical like powerpacks,,or the coils,, or the stator.even the boat place couldnt even figure it out.had it nine weeks in is shop.and gave up. im totally lost on this matter<br /><br />thanks for your input

 

[Liam]

Re: 85 hp force wont start just backfires

Milkman, check the firing order. I don't know how many cylinders you have but it sounds like it wants to go but is out of timing (hence backfire). If timing is set correctly mark the plug wires to each cylinder and try a different combination. If it does not work you can always put them back to their original position.<br /><br />Good Luck <br /><br />Liam

 

[Liam]

Re: 85 hp force wont start just backfires

Milkman, one other idea. Are the valves moving? If the valve are not moving an exhaust valve could be wide open permanently. If this is the case the engine will turn over much more quickley than it usually does.<br /><br />Any other information you have will help, like what did the shop do, why it took them 9 weeks, did you change the head gasket yourself, etc.<br /><br />Liam

 

[kev_79]

Re: 85 hp force wont start just backfires

Liam,<br /> 85 Force is a 2 stroke. No moving valves, just ports that are covered and uncovered by piston moving up and down. <br /><br />By the way, how did you get your screen name? Is it your real name? Just wondering.<br /><br />Kev

 

[JB]

Re: 85 hp force wont start just backfires

Ahoy, Milkman. I think someone has made a small error that is more common than you might think. I haven't met anyone (except a guy in a mirror) who will admit to this, but I think your plug wires are on the wrong plugs.<br /><br />Turn her through by hand with the plugs out and the ignition on. When a plug fires, stop. Peek into the cylinders and determine which is nearest TDC. That's the one!. Continue until you have all wires on the correct plug.<br /><br />Good luck.<br />Red sky at night. . .<br />JB

 

[milkman]

Re: 85 hp force wont start just backfires

thanks guys for your replys. this board is the best thing since bubble gum.i have tried all of the above changing the plugs wires around and around.and i beleive they are right where they need to be. they are staight across from plugs in order,thats where they were when it ran.also it was in the shop where they put a timing light and they said it seem to in time.the shop i took to here in town works on force motors regularly said he has never had this much problems getting a motor to at least start. he had it for nine weeks. granted he didnt look at everyday,he kept pushing it to the because he was stumped. he had checked the compression and on one cylinder was a little low so he changed the head gasket on it.he also said it was getting good spark on all the coils. and it was getting fuel, but when it tried to start it just backfires through the exhaust.so the mechanic gave up luckly he felt bad for having the boat for so long he only charged me 20.00 dollars for replacing the head gasket.he also changed the flywheel on it. but it didnt do any good.<br />so anyway i have taken it to another shop they have a lot spare parts off dead force motors there they can swap parts to troubleshoot this thing.my whole summer is down the drain.<br /><br />kev_79 milkman was given to by a friend i work with he said i was milken this job,because i was taken so long. and it just kinda stuck with me now <br /><br /><br />anyway guys thanks for your input on this matter i love this board im addicted to it now.with having this force il probally be here alot. if anyone has more idea's please let me hear from you. and when i find out whats wrong with this motor i'll let you all know<br /><br />thanks again <br /><br />milkman

 

[milkman]

Re: 85 hp force wont start just backfires

hello fellow boaters<br />i have an update to make it appears that its something to do with the ignition system. some kinda trigger mechicnism under the flywheel, they tell this ignition system was only used one year , because it became a problem child right off the bat.they also told me it has to be shipout somewhere to be repaired.its gonna cost between 500.00 to 600.00 to fix ouch!!!. they told me that this trigger mechicnism tells the number one cylinder when to fire. thats why its firing out of order causing to backfire.i also was wondering if they had upgraded this part or am i just screwed. <br /><br />i just wanted to let all of you to know so maybe in the future you can help out another poor soul like myself out.also any comments on this matter i would appricate.<br /><br />i hope this will help you guys in the future<br /><br />thanks again for all your help<br /><br />milkman

 

[Charles Burkhardt]

Re: 85 hp force wont start just backfires

I have a 50 HP Force which backfired through the exhaust. Turned out that I had the wires from the triggers going to the wrong coils. In my engine there are 6 wires from under the flywheel, and each coil has 5. I can tell you how mine are hooked up if you e-mail me direct at cburk001@juno.com