Force 70 heavy start up

[joebart]

Last fall I bought 1994 Bow rider with 70 hp Force outboard. I did not have a time really to test before winter come. This year I have a problem with unpredictable heavy startups. Once its running runs well.
That how it goes:
Pump primer hard. Press center button on the control to have some acceleration on the engine. Press key for choke and start. Bendix ( pinion) goes up, tries to turn the fly wheel and falls down still spinning. No go? I flushed the engine OK, checked spark plugs, and cleaned them OK. Recalibrated idle speed OK. No luck. Now I think I might have problem with starter itself or wiring leading to it or solenoid valve since my pinion (the old one broke, to many tries) drops down from fly wheel too early maybe due to drop of the voltage along the way. Any suggestions?
Joseph

 

[Jiggz]

Re: Force 70 heavy start up

First things first. Check battery is fully charge. Disconnect both the main ground cable and positive cable from battery and engine block and starter solenoid. Wire brush and sandpaper both end terminals until very clean. Do the same with the engine block connection and also with the solenoid terminal. Re-connect. Apply light grease on starter shaft and also on bendix gear. Try again. Remember if the bendix keeps dropping off because the engine coughs or tries to fire, that is perfectly normal, which is by design. If the engine just keeps "coughing" it could be the fuel is sour or idle mixture setting is too low. However, make sure you follow starting procedures correctly. Remember, after the first choke and the engine "coughs", you shouldn't choke it again but rather just start normally without choke and crank it to at least 5~10 secs. After two or three tries it is still no go, then try choking it again. If you continually choke evertime you start, you will flood the carbs seriously making it harder to start the engine.

 

[joebart]

Re: Force 70 heavy start up

First things first. Check battery is fully charge. Disconnect both the main ground cable and positive cable from battery and engine block and starter solenoid. Wire brush and sandpaper both end terminals until very clean. Do the same with the engine block connection and also with the solenoid terminal. Re-connect. Apply light grease on starter shaft and also on bendix gear. Try again. Remember if the bendix keeps dropping off because the engine coughs or tries to fire, that is perfectly normal, which is by design. If the engine just keeps "coughing" it could be the fuel is sour or idle mixture setting is too low. However, make sure you follow starting procedures correctly. Remember, after the first choke and the engine "coughs", you shouldn't choke it again but rather just start normally without choke and crank it to at least 5~10 secs. After two or three tries it is still no go, then try choking it again. If you continually choke evertime you start, you will flood the carbs seriously making it harder to start the engine.

Thank you for that advice. I cleaned all connectors and the bendix is almost up there slightly going up and down but not dropping off while cranking. Still no go? It seams I have lost a spark on all cylinders now. I have downloaded some troubleshooting tips trying to pin point the problems. This time is not the gas or the starter. It could be a stator, trigger, voltage regulator, or the switch box (ignition module by Mercury).
So far by disconnection of black/yellow wire at switch box (the pack) I have eliminated stop circuit. By disconnection of the yellow wires from rectifier (voltage regulator) I have eliminated voltage regulator problem. Now what I have left is to test stator ohms and volts, trigger assembly and if that is all good will be left with faulty switch box. But that is for tomorrow. I will let you know? Once more, thanks for the advice.. Joseph

 

[jerryjerry05]

Re: Force 70 heavy start up

First do a compression test.
Load test the battery.
The gas, check for water.
The carb, the air screws set at 1 turn out for initial setup.
Take the starter apart and clean the brushes and armature.

 

[joebart]

Re: Force 70 heavy start up

Removed stater today. Its original part 398-8778A28. Have a resistance of 100 ohms between ground and red wire. No reading between ground and blue wire. Looks like open circuit. Should have about 3500 ohms so I guess its faulty. After market replacement for it is DCI 174-8778K1.
Am I right?

 

[joebart]

Re: Force 70 heavy start up

Ordered new stator from Wholesale Boating Supply NC. It was send on Monday August 19 and it still did not leave up to now Sorting Warehouse of US Postal Service in NC. Good work USPS It will arrive in Canada right for Christmas....

 

[joebart]

Re: Force 70 heavy start up

Received new stator and installed it. Engine fires with no problem at all but it rough-run at idle speed and have some misfire. I am discouraged.... :-(

 

[Jiggz]

Re: Force 70 heavy start up

Verify you have sparks on all cylinders. If you do, make sure you have idle mixture setting correctly (1 turn out from slightly seated or even up to 1 1/8 turn out). Make sure you are idling around 1000~1100 RPM on muffs. If it is still rough idling, do a compression test and repost.

 

[joebart]

Re: Force 70 heavy start up

Dear Ensign.
Cylinder 1 was wet despite voltage going to spark plug. Faulty spark plug. Replaced,. Engine running OK but getting occasionally sneeze to the carburetor. I guess it could be timing problem. Did not check compression yet. waiting for the tool. Did not test on the water since Georgian Bay is just roaring for a week..waves are jut a little to big for me..

 

[Jiggz]

Re: Force 70 heavy start up

We'll wait until we can verify compression. Is the sneezing only occasional like only when starting? If it is constant it could be a timing problem.

 

[joebart]

Re: Force 70 heavy start up

Well, I took the boat yesterday for a run. It still had a problem running at low RPM so I had to increase idling speed a little. It sneezed once or twice which is not very good for a fuel pump but it run for a few hrs. Not too bad.
Now comes the bummer, I got a toll for cylinder compression test, grounded high voltage wires and run the test. I am screwed, cylinder 1 (30psi), cylinder 2 (125psi), cylinder 3 (125psi).
Basically I never had cylinder 1, I am devastated. Put the plugs in and tried to start the engine. No go at all. LEMON . I did covered the boat and walked away…….

 

[Jiggz]

Re: Force 70 heavy start up

Now that explains low idling and why the motor dies when placed in gear. It's not all lost though unless the cylinder is really messed up. Changing piston is not really as hard as you might think. But before delving into it, search "piston replacement" on this forum and you will be surprised how easy it is. This is as long as you have the patience, time and a little money to do it. You can actually replace that piston, assuming the cylinder is not too messed up for less than $250.

 

[joebart]

Re: Force 70 heavy start up


Well, I removed head from the motor and surly I found some damage to the first cylinder due to I guess broken piston rings (picture). I also removed carburetor and intake manifold to get access to connecting rod screws. I did not managed to remove piston so far since I have problem with sizing proper socket wrench. It has to be a thin wall. 1/4 is to small, 1/16 too large. Any idea? Do I need something special ?
The scars on a cylinder seems to be not that bad and fixable. Any suggestions?

 

[joebart]

Re: Force 70 heavy start up

I think I need something like E-Torx socket but not sure about size.

 

[Frank Acampora]

Re: Force 70 heavy start up

It should be a 1/4 inch 12 point socket, 1/4 drive. Six point sockets will not fit. Buy one at Sears if you have them up there. If not, any good tool store will have them

 

[joebart]

Re: Force 70 heavy start up

I have removed piston from the engine, booth rings were cracked and partly missing, some burn-out damage to the piston. I managed to get hold of used standard size piston in a good condition. Does anybody know easy way of removing pin from the piston and instilling it into undamaged one? The pin is very tight but mostly it is on the spacers and not on the piston itself. Tomorrow I will attempt to hon the cylinder without actually removing it from the engine. I will block all channels and the crankshaft and with honing tool I will try to fix cylinder as much I can. Also when I removed piston and halves of roller cage I counted 14 rollers so it don not seems to me there are no roller in the connection between the cages. Am I right? Thanks for help. I appreciate it…

 

[Nordin]

Re: Force 70 heavy start up

As it is a 70Hp 1994 I am not so familiar to it. BUT all Chrysler and Force I have worked with have had 16 rollers at each rod.
There are one roller between the cages at each side.
You seems to missing 2 rollers. Check in the crankcase for the two missing rollers.

 

[jerryjerry05]

Re: Force 70 heavy start up

If you can scratch the grooves in the piston and can feel it you probably need to bore and get a bigger piston.
To push the piston pin out, you will need a press.
Just bought one(20 ton) from Harbor Freight.
Put the 2 halfs of the bearing cage together.
Then count the holes.
Like Nordin says, the bearings on all I've worked on are 16.
Try not to use a magnet.
If you leave them on the magnet, they get charged and can actually draw metal shavings and lead to failure.
If you use grease to reassemble? Use "bearing assembly grease" it holds them in place and melts fast.
Marine grease or triple guard won't melt as fast and can actually burn the bearings.
Lots of guys use triple guard, the manual says not!

 

[joebart]

Re: Force 70 heavy start up

All marina mechanics wanted about $100 to replace piston (labor only to push the pin out and in) With the help of a friend , big vise, torch, coupe of pins, pieces of wood and a lot of luck, we manage to replace the piston on a connecting rod in under an hour. Honing cleaned most of the scratch in cylinder except 2 to 3 mm at the and of cylinder. I am going to reassemble everything in a day or two and see if I am lucky. Am I able to reuse head gasket, looks very good. I understand it should be replaced but budget is a budget. $37 gasket becomes $100 after the shipping and taxes. Is it possible?

 

[Jiggz]

Re: Force 70 heavy start up

Yes, it is OK to reuse the head gasket as long as you can validate it is in excellent condition. In fact, it is even recommended since you would not have to re-torque the head thereafter. Note the hardest part of the assembly is aligning the piston rod caps to the crank journal while ensuring the roller bearings stays. I've used a 1/4" rod long enough to come from the carb's end and inserted through and aligned to one of the cap bolt holes before inserting the piston into the cylinder. In this manner the rod serves as a carrier to the cap and aligns it to the journal. A two man team can do this quicker. After the top cap is aligned to the journal do not remove the rod yet, instead use it to align the bottom cap by passing it through the bolt hole also. As for grease to hold the rollers, others went as far as freezing light grease to stiffen it. I used triple guard and never had problems just make sure you do not use an enormous amount just enough to hold them in place.