1985 Mercruiser 140 Won't Start or Manually Turn.

[lmorefield41]

Ok, so I bought a 19ft open bow, 1985 4 Winns Horizon 190 with an I/O Mercruiser 4 cyl 140, 3.0. I bought it for half the price the guy was asking because he swore it would start, but I was unable to start it, therefore I wasn?t paying what he was asking. It sat in his driveway for 2 years, as he became disabled due to 3 separate surgeries. The cover became torn and sunk in from the weight of leaves and snow; therefore it got rained and snowed in for 18 months or so. The entire interior needs replaced, however that?s not the issue and is the easy part for me to do. I already have it stripped out and it?s all ready to be redone, but I am not going to go any further until I can figure out what?s going on with the motor. So this is my question and problem for you guys: I cannot get the motor to start. I?ve read so many posts and threads from this forum with no solid lead. The battery is brand new and is giving off 12+ volts. I?ve cleaned all of the terminals on the wiring and have made sure the connections are solid. My initial thought was that the starter was bad, simply because when I tried to start the motor, there would be a loud violent clank, but the engine would not turn over or crank. Notice I said loud ?clank,? not crank. I tried to keep the key turned and started to see smoke coming from the battery leads, and then noticed they actually melted a little bit. When turning the key, nothing happens except the loud clank, and then the battery heats up upon holding the key turned. Thinking it was the starter; I removed it and the slave solenoid (the smaller one that?s mounted underneath the circuit breaker) and had them tested at AutoZone. Both passed the tests stating they were both in good shape and fully functional. After finding this out, I read some more posts to see what I could find. I started to troubleshoot other parts of the engine. I tried manually turning the engine, to no avail. I removed the spark plugs as I read to do in a post, still no avail. I put a breaker bar on the alternator pulley, just to have it spin freely without the belt moving, although the belt is super tight. I am now thinking that the engine is seized, and that the loud clank from trying to start the engine is from the starter trying to engage the flywheel and becoming stopped traumatically. Does this sound logical at all? I have not taken off the outdrive yet, which is my next step from reading a post. What I have done is spray WD-40 in each of the cylinders through the spark plug holes. What advice do you guys have for me? Each and any advice will be a great amount of help, as well as greatly appreciated. Sorry for the novel above, but I wanted to be as descriptive as I could possibly be.

 

[Bt Doctur]

Re: 1985 Mercruiser 140 Won't Start or Manually Turn.

try removing the drain plug in the pan or pump some out the dipstick. Motor may have filled with rain/snow melt,remove the drive to isolate the problem.drive may be siezed.
remove the head to inspect head and bores.
Get a used input shaft and weld a T handel to it to try turning the motor thru the coupler

 

[lmorefield41]

Re: 1985 Mercruiser 140 Won't Start or Manually Turn.

remove the drive to isolate the problem.drive may be siezed.

If the drive is seized, does this mean I'll have to replace the drive?

 

[Fishermark]

Re: 1985 Mercruiser 140 Won't Start or Manually Turn.

If the drive is seized, does this mean I'll have to replace the drive?

Possibly, but one problem at a time.

Given what you have said about the condition, the chances are good that it is the engine, not the drive. By all means, go ahead and remove it - there are some good maintenance / inspection things you can do at that time anyway.


What did the plugs look like when you pulled them? Rusty? Instead of spraying WD40 in the cylinders, try pouring some oil or transmission fluid in them instead.

If it were me, given how easy it is to pull the head on that engine, I would do as suggested by the doctor and pull it to find out more specifically what is going on in the cylinders.

 

[lmorefield41]

Re: 1985 Mercruiser 140 Won't Start or Manually Turn.

What did the plugs look like when you pulled them? Rusty?

The plugs were carbon fouled, they weren't rusted, except for the outer part where they screw in at. However, the #2 plug did have a small amount of a green substance that looked similar to anti-freeze. So overall, they were in decent shape, however, I'm replacing them for sure.

If it were me, given how easy it is to pull the head on that engine, I would do as suggested by the doctor and pull it to find out more specifically what is going on in the cylinders.

I will get to this asap.

 

[lmorefield41]

Re: 1985 Mercruiser 140 Won't Start or Manually Turn.

Hey, I don't mean to be ignorant, but as far as removing the head, is it as simple as removing the rocker cover, then the head bolts, and thats it? Do I have to remove the rocker bolts and rockers as well? Also, when I took the rocker cover off, I noticed that one of the valve spring sheilds is missing from the valve spring. The spring does not look damaged at all. So with that being said, will it be ok in this condition?

 

[stackz]

Re: 1985 Mercruiser 140 Won't Start or Manually Turn.

the exhaust is hooked to the head and then to the outdrive...so if the exhaust is still hooked up, the head wont come off unless you're hercules.

also, hoses, etc will be connected and have to removed to get the head off. but yeah, if you can get to all the bolts without moving the rockers, you can pop the head off. not recommended though as the pushrods will just fall all over the place. loosen the rockers and move them to get at the pushrods and remove them before popping the head off.

 

[lmorefield41]

Re: 1985 Mercruiser 140 Won't Start or Manually Turn.

so if the exhaust is still hooked up, the head wont come off unless you're hercules.

So does the exhaust have to be unhooked from the outdrive side as well, or just from the head, in order to remove the head?

 

[Fishermark]

Re: 1985 Mercruiser 140 Won't Start or Manually Turn.

Pull the outdrive first to take that out of the equation. After pulling the outdrive, see if the engine will turn over manually.

If not, then you can pull the head. Basically everything attached to the head needs to be removed. Remove the riser from the manifold, as you will want to look at the condition of both. There is a rubber boot that the riser will slip into - the clamp will need to be removed.

Then you can remove the exhaust manifold. Everything else is pretty straight forward from there. As mentioned above, you will need to remove the push rods. Be sure to keep them in order as they will need to be put back in the same holes with the same lifter and rockers.

 

[lmorefield41]

Re: 1985 Mercruiser 140 Won't Start or Manually Turn.

Thanks for the info, I will get after it as soon as the rain wishes to stop.

 

[lmorefield41]

Re: 1985 Mercruiser 140 Won't Start or Manually Turn.

Ok, so I have the outdrive pulled out, I'm in the process of welding a handle to an input shaft so I can try and turn the motor through the coupler. When I pulled the outdrive out, the u-joints and the base of the shaft, the part closest to the u-joints, appeared to be rusted. Is this a sign that means the bellows need replaced? I plan on trying to move the motor through the coupler before I take the head off.

 

[Don S]

Re: 1985 Mercruiser 140 Won't Start or Manually Turn.

With the outdrive off, just remove the spark plugs. The engine should then turn easily by just turning the nut on the alternator (tighten the belt if needed)

 

[lmorefield41]

Re: 1985 Mercruiser 140 Won't Start or Manually Turn.

With the outdrive off, just remove the spark plugs. The engine should then turn easily by just turning the nut on the alternator (tighten the belt if needed)

I tried doing this, the alternator just slides. I've tried tightening the belt as tight as it goes. Still nothing. I can't get a grip on anything else. With the flywheel on the opposite end, should I be turning the pully CCW, or CW?

 

[lmorefield41]

Re: 1985 Mercruiser 140 Won't Start or Manually Turn.

So I've welded together u-joints and an input shaft, however, it isn't long enough to actually grip the splines or turn it through the coupler. Any advice on this? I need to change the bellows anyway, so can anybody help me out with a manual or instructions to do this? I think if I get the bell housing off, I can reach the shaft with a pipe wrench. Thanks for the help.

 

[Fishermark]

Re: 1985 Mercruiser 140 Won't Start or Manually Turn.

If the engine is seized enough that it will not turn easily with the plugs out, then you have bigger issues. Yes, you will be able to get a little closer access to the coupler with the bell housing out of the way, but again, it sounds like you are going to end up disassembling this engine anyway one way or another.

 

[lmorefield41]

Re: 1985 Mercruiser 140 Won't Start or Manually Turn.

If the engine is seized enough that it will not turn easily with the plugs out, then you have bigger issues. Yes, you will be able to get a little closer access to the coupler with the bell housing out of the way, but again, it sounds like you are going to end up disassembling this engine anyway one way or another.

Is there any instruction manual on how to do this exactly? I know how to easily do this on some car motors, however, never have done any work on anything this old. Also, when I do get the head off, what should I be looking at/for? Is there anyway to get the engine to move after having the head off? I don't think it's that bad, I just can't grip anything. The alternator pulley keeps sliding, no matter how tight I get the belt. Then with this input shaft, it's just not long enough.

 

[Bondo]

Re: 1985 Mercruiser 140 Won't Start or Manually Turn.

Is there any instruction manual on how to do this exactly? I know how to easily do this on some car motors, however, never have done any work on anything this old. Also, when I do get the head off, what should I be looking at/for? Is there anyway to get the engine to move after having the head off? I don't think it's that bad, I just can't grip anything. The alternator pulley keeps sliding, no matter how tight I get the belt. Then with this input shaft, it's just not long enough.

Ayuh,.... Pull the motor...
It's easier to work on, on a stand, or even the shop floor...
besides, the motor is easier to pull, than rippin' apart the transom for no other reason at all...

 

[lmorefield41]

Re: 1985 Mercruiser 140 Won't Start or Manually Turn.

Ayuh,.... Pull the motor...
It's easier to work on, on a stand, or even the shop floor...
besides, the motor is easier to pull, than rippin' apart the transom for no other reason at all...

Thanks for the info Bond-o. I appreciate it.

 

[Fordiesel69]

Re: 1985 Mercruiser 140 Won't Start or Manually Turn.

Before going thru the labor to pull the motor, pull the manifold off it and observe the outer block casting real close for any cracks. If there are cracks anywhere, you can stop now and begin your search for a replacement engine. If you go thru all the bother pulling it and find out its bad, then all winter long, parts are going to get lost, you will forget which wires go where, etc. If motor is seized, you are looking at a full rebuild or full replacement.

 

[Leedanger]

Re: 1985 Mercruiser 140 Won't Start or Manually Turn.

Ok, so I have the outdrive pulled out, I'm in the process of welding a handle to an input shaft so I can try and turn the motor through the coupler. When I pulled the outdrive out, the u-joints and the base of the shaft, the part closest to the u-joints, appeared to be rusted. Is this a sign that means the bellows need replaced? I plan on trying to move the motor through the coupler before I take the head off.

I didn't see this part of your question get answered but I'd say that yes you should do the bellows, U-joint socket centers, and gimbal. The U-joint bellows should certainly be sealed so my guess is rust=bad. If your gonna go this far with this project I would certainly fix all of that anyhow. Check out this link for parts, this guy treated me well and it's a great price: http://www.ebay.com/itm/Mercruiser-Transom-Bellows-Kit-Gimbal-Alpha-1-U-JOINT-/220800805647?pt=Boat_Parts_Accessories_Gear&vxp=mtr&hash=item3368c0eb0f#ht_835wt_1189 I don't think you'll find it all that difficult to pull that motor either....putting it back in can be a little bit of a chore if your by yourself or don't have an A frame. Good luck.