starting issue with 83 115 merc

[Nickledimed]

While trying to start the engine.
I turn the key, starter engages, engine rolls over, engine coughs, starter disengages, engine does not start.
Or; I turn the key, starter engages, engine starts to roll over ( no cough), starter disengages, engine does not start.
At first when the engine is cold the engine will turn over easily.
The engine is getting fuel, ...it flooded while trying to start it.
I figured it was getting fire at one time becouse it would caough.
any ideas on this?...Ive got a repair manual on the way in the mail.
Thanks for the help.

 

[OldMercsRule]

Re: starting issue with 83 115 merc

Sounds like trouble in yer starter drive.

Could also be a weak battery, (you need a big group 27 or 24 fully charged battery with a lot of cranking amps NOT A DEEP CYCLE to properly crank these inlines).

The strarter must engage sufficiently to turn your engine over at a fair speed to properly start (a well primed with fresh mid grade premix 50-1 fuel) cold engine, if the starter disengages prematurely you will always have trouble starting a cold inline6 Merc.

My overpriced $.02. JR

 

[Nickledimed]

Re: starting issue with 83 115 merc

thank You for your response.
I will purchase a big group 27 or 24 batt and drain my tank and put a mid grade octane 50:1 mix in it...Ill keep you posted.
PS. Could you recomend a brand and or place to get one of these types of batteries?

 

[OldMercsRule]

Re: starting issue with 83 115 merc

thank You for your response.
I will purchase a big group 27 or 24 batt and drain my tank and put a mid grade octane 50:1 mix in it...Ill keep you posted.
PS. Could you recomend a brand and or place to get one of these types of batteries?

Costco or Walmart (no particular brand as Johnson Controls or Exide makes many of them) just look at the cold cranking amps, (CCA) at 32 degrees group 27 is for a Ford Truck group 24 is for a large older v-8 automobile. Those are two of the larger, (physical size) batteries I know of. Look for the biggest batery at Walmart with the most CCA, (within reason for the money). Get the marine type battery so the wing nut terminals are on it in addition to the conventional battery posts (and it should have a strap for carring it in and out of the boat).

Is the gas old in your boat tank?

You may want to get a plastic six gallon tank and new Merc gas line to put the fresh mid grade pre mix at Walmart while you are buying the battery. I don't know why you need to drain the tank unless the fuel was not stabilized and or it is really old.

If the real strong fully charged battery doesn't kick the starter and keep the engine engaged and really cranking you may need to trouble shoot the starter, (look at the amps drawn when you crank it and or the starter drive mechanizm which may need replacing).

Good luck. JR

 

[Nickledimed]

Re: starting issue with 83 115 merc

I went out and looked at the batt, its an everstart wm24....when I was first hitting the starter the starter turns the moter over pretty strong.
If holding the starter down you could almost propel the boat just with the starter.....untill it started disengaging right away.
The starter looks like it was replaced pretty recently also.

As for the gas: I think your dead on about the gas, its old and I was being cheap and lazy.
It looks like its got a new fuel line on it, the bulb is nice and soft.
It looks like it had a tune up within the past 2 years, Im going by this by looking at the plugs, plus I found the old plugs and some parts in the glove box.

I just bought this boat.
I dont think it has been taken care of very well in the past year or so.

you can see the boat here
http://i39.tinypic.com/28gz15k.jpg

Thanks for the advice, Ill keep ya posted.

 

[OldMercsRule]

Re: starting issue with 83 115 merc

Yer group 24 battery sounds like it is big enough if it is in good corndition and fully charged, (so hook it to yer battery charger to top it off). What is the rating in CCA?

Did you start the engine and or check the cornpression of the 26 year old engine prior to purchasing the boat? That is a must.

If you didn't you must fix one thing at a time to see if the engine runs properly.

The boat and engine looks very nice in the picture so don't pannic.

If you have a built in tank with fuel of unknown age and corndition I would drain it. Solve the starting issue first which is the battery or the starter as I explained above. Make sure the battery cables are in good working order. Once you get it to crank steadily where the engine turns over rapidly then you can deal with the cornpression spark plugs/ignition and fuel system issues if you have further problems.

Don't fix things that aren't broken yet. The starting issue you identified is job #1. You might try some lubricant like WD-40 or some such on the starter mechanizm at the top of the starter.

Good luck. JR

 

[Nickledimed]

Re: starting issue with 83 115 merc

The boat came with 3 batteries.
I took all 3 to autozone and had them checked.
2 were good, one was bad.
On the 2 that are good the CCA is 525 and 500, are these sufficient?
Im going to get some gas this afternoon and give it a shot.

 

[OldMercsRule]

Re: starting issue with 83 115 merc

The boat came with 3 batteries.
I took all 3 to autozone and had them checked.
2 were good, one was bad.
On the 2 that are good the CCA is 525 and 500, are these sufficient?
Im going to get some gas this afternoon and give it a shot.

I don't think those are big enough, (one of the "big guns" posted the battery size requirement fer an inline6 very recently so search this part of the forum about batteries.

That maybe why you have a starting issue and it could have harmed the armiture on yer starter, (dunno yet).

If you charge them with a fresh charge, and jump them together (WITH VERY GOOD JUMPER CABLES), you may get enough snot to start her and check out the starting circut. Jump the second good battery directly to ground on the block and the hot side of the solinoid, (not the starter side).

Remember to inspect and clean the terminals on both batteries and the battery cables, make sure the solinoid ends are clean and tight as well, (and the hot cable to the starter from the solinoid).

As I said I would get a six gallon tank and new gas line with fresh 50-1 pre-mix mid grade, (hopefully without ANY alcohol), as a built in tank with unknown garbage in it could cost you a lot of money and pain if you load yer engine with junk or water, (or both).

I would never hook one of my inlines to a fuel system of unknown cleanliness with fuel of unknown age and unknown pre mix.

Good luck. JR

EDIT BTW: I bet that little 15 footer will scream if the engine is in good shape, WHAT IS THE USCG RATING FER THAT HULL, (MAX HP?). Ya better be carefull as those old inlines really get up and go.

 

[Nickledimed]

Re: starting issue with 83 115 merc

Dumped old gas, got 5 gal of 91 oct with mix.
Checked charge on the batt with the 525 cca rating.
Engine turned over, coughed died...did this several times, batt was getting low, gabbed my booster/charger and set it to 50amp start mode.
Engine fired right up, idled, reved to about 1500rpm, engine returned to idle.
put lower unit in gear,...successfull!
shut engine off, then started right up with no problem!
This engine runs good as far as I can tell, we will see when I get it on the lake.
But I think it will be fine.

As far as the hull rating, Im not sure, the plate is so faded I can only make out that this boat has a 6 passenger rating.
I would love to find out all the specs are for this boat but so far I only know that its a thundercraft and that it is an 83 model.
I still beleive the moter is too big for the boat but not sure.
Im not complaining though..for 850 dollars Im just tickled to get something I can fish out of...anything else I can do with it is a +.
Thank you for all your help!!!
Next Ill be working on the decking and what not.....I need seats

 

[nativetexantim73]

Re: starting issue with 83 115 merc

Hey bud you want to use a 725 CCA or higher when using on a Inline 6. I have the same motor .

 

[Nickledimed]

Re: starting issue with 83 115 merc

Hey bud you want to use a 725 CCA or higher when using on a Inline 6. I have the same motor .

Ty for the info.
Ive got my eye on an 825cca everstart maxx at walmart for 78 dollars.

 

[OldMercsRule]

Re: starting issue with 83 115 merc

You only need 89 octane, (any higher is a waste of money and less power output). If you can get non alcohol fuel, (straight dyno), that would be worth spending some money on. You may wish to run sea foam in the first tank of gas to decarb the power head.

I bet the hull is overpowered so be carefull. You may want to check the transom strength by trying to make it move from the bottom of the skag on the engine when on the trailer, (if it moves you got a problem that shouldn't be ignored on an overpowered boat).

I would also replace the lower unit fluid with marine grade gear oil. Hope you have a tach so you can verify that you are proped for WOT @ 5,500 to 6,000with a light load, (if ya can run it that hard and live to tell about it).

Glad to hear it worked out. Good luck and happy boating. JR

 

[Nickledimed]

Re: starting issue with 83 115 merc

Double posted...sorry

 

[Nickledimed]

Re: starting issue with 83 115 merc

Just checked the trasom and its solid as a rock.
I agree, its a very light boat, would you suggest me adding some weight to it?
If so, were? forward, aft, center?
The forward section is pretty hollow.
I dont have a tach, any suggestions?
Im not sure what you mean by being proped for WOT @ 5,500 to 6,000with a light load.
The guy I bought this from said he ran it last year, tubeing and skiing with no issues. the reasone he sold it was becouse he bought a new one.

 

[nativetexantim73]

Re: starting issue with 83 115 merc

WOT means Wide Open Throttle. So He means that with the load that will be in the boat, the throttle wide open the correct prop shouldn't allow the motor to turn faster than 5500 to 6000 rpms. Lower than that could cause detonation in the cylinders and higher than that the engine could come apart. Happy Boating!

 

[NFA]

Re: starting issue with 83 115 merc

My first boat was a 14' aluminum with a 35hp Johnson on the back. It was overpowered for the boat and I put two cinder blocks in at the front of the boat to weigh down the bow. Weight distribution depends on where the weight that is already in the boat, is currently located. My aluminum was a tiller so I was sitting at the back, therefore more weight at the back. So I needed the additional weight at the front. Consider where all your weight (you, passengers, gear, batteries, gas tank, etc) is right now, and add additional weight accordingly.

And get a better, more powerful battery. The piece of mind for starting that engine is worth the extra money, not to mention the embarrassment of sitting at a launch trying to fire the damn thing up while loads of people are waiting and watching.

Can you tell this is coming from experience.



SSS

 

[OldMercsRule]

Re: starting issue with 83 115 merc

Nah don't ever add weight to a boat just to add weight.

(WOT = wide open throttle).

Get a tach and hook it up, (the port on the forward end of yer Merc corntrol is where you hook it up). A tach is essential to proper operation and life of an inline 6, IMHO.

If the engine is proped to run @ 5,500 to 6,000 RPM @ WOT with a light load it will never lug and destroy the engine with various loads and operating cornditions over time.

I'd suggest you do some reading of the posts about inline6(s) in this forum.

Good luck and enjoy. JR