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1975 85hp Johnson starter mount broken

G

GaryOutland

Contributing Member
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This starter mount is broken. Would JB weld be my best option. The cause of this is due to the top front bolt backing out, putting too much pressure on this mount.
 
My buddy Wes put his magical touch on it. He was able to TIG weld it. After replacing starter, 2 coils and cleaning carbs, l finally got it cranked. This is a project boat that will hopefully be a fun river cruiser.

The starter spins engine very good, but just as engine starts to fire,starter Bendix releases before engine starts. I must release key and try again. Sometimes as I turn the key to start position the Bendix goes in and out of flywheel as engine tries to start. Any thoughts? I will be changing plugs next.
 
check for voltage drop between batt. and solenoid then between sol. and starter,12 volts should be present. if not pull connections and clean all connecting points,check all wiring with ohm meter.
 
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With all spark plugs installed, having the bendix gear jump out of the flywheel even if no ignition is engaged... that is normally caused by a fairly large difference in compression between cylinders.

If the bendix jumps out ONLY when trying to start (Ignition ON), carefully check the engagement of the bendix when it is fully engaged into the flywheel teeth. The heli arc weld may be ever so slightly off (too loose?)... if so, install a "THIN" washer (shim) between the bottom retaining bolt hole and the block to ever so slightly tilt the bendix gear further into the flywheel teeth.
 
Thanks Joe. I will take close look at that. With no fuel it spins really well and even, as if compression is equal. Bendix only drops out when a cylinder fires, but not enough "kick" to keep engine running. Occasionally the Bendix will go in and out of flywheel if you hold key in start position. Again this only happens when 1 or more cylinders are firing w/o engine actually starting. I plan do do compression test, and check timing, and new plugs.

I was just trying to get it to crank to see if it is worth sinking money into, and it seems like a worthwhile project.

Thanks Again for all of the help.
 
The general timing is set via the flywheel key keeping the flywheel in perfect position with the flywheel key slot. If the key shears, even ever so slightly... the engine will be out of time and simply will not run. Factory torque setting for that flywheel nut is 105 foot pounds.

The spark advance timing will not be far enough ahead to affect the cranking and starting as you would need to have the throttle at least half way open to approach that point.

However, if you come across something odd within the timing, let me know (weird things happen).
 
Although the two pictures are decent and clear, it's still hard for me to say definite one way or the other, however, I don't think so.

Hopefully a few other members will jump in here with their opinions.
 
I just did something that I should have done first. Compression test!
Cylinder 1. 80 psi
Cylinder 2. 140 psi
Cylinder 3. 60 psi
Cylinder 4. 135 psi

I looks like I have a problem with 1,3 bank.
 
I just did something that I should have done first. Compression test!
Cylinder 1. 80 psi
Cylinder 2. 140 psi
Cylinder 3. 60 psi
Cylinder 4. 135 psi

I looks like I have a problem with 1,3 bank.

The head gasket appears to have been replaced ( I bought this used, with no knowledge of previous condition). The gasket that is the uppermost gasket, closest to the plugs looks to be original. Could this gasket cause compression problems? I did put a little oil in cylinders,but no change in compression, so I am thinking that I am loosing compression in-between these 2 adjacent cylinders.
I previously posted that starter disengages when engine fires,but does not start. I was told on this forum that unequal compression could cause that.

Engine will crank and run with no load, but dies immediately when put into gear. Lower gears and bearings are free.
 
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As for starter voltage issues, I did replace battery cables. I think that the battery, although it is new, is not holding a good charge.
 
You state: "The gasket that is the uppermost gasket, closest to the plugs looks to be original."

Sorry, I have a problem understanding that statement. However, the head gasket needs to be removed in order to inspect the head and block sealing surfaces, etc.
 
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The head gasket appears to have been replaced (left finger in picture). The head cover gasket (right finger in picture) is original. Is it possible for head cover gasket to cause low compression on 2 adjacent cylinders? Or a better question could be what typically causes adjacent cylinders to both have low compression.
 
start with a good batt. Do another compression check if starter issue is gone.proceed with joe reeves thread if readings are still awry.And yes bad gasket can cause your symptoms. Low comp. between cylinders is common with break in head gasket.
 
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GaryOutland said:
View attachment 13471 The head gasket appears to have been replaced (left finger in picture). The head cover gasket (right finger in picture) is original. Is it possible for head cover gasket to cause low compression on 2 adjacent cylinders? Or a better question could be what typically causes adjacent cylinders to both have low compression.
Click to expand...

Okay... that I can understand. The upper and lower mention was confusing... better to use a inner and outer description. FYI the main head gasket is just that... a "Head Gasket", the other gasket on top of the head is called a "Water Jacket Gasket."

A failed head gasket can affect both cylinders on one bank if it should fail at a point between the cylinders, usually caused by not being torqued down in sequence properly.
 
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Thanks Joe. The correct terminology does help. Do you think I should leave water jacket gasket alone and pull head to check head gasket and head and block surfaces?
 
Yes pull the cylinder head for inspection.--Or the # 1 , 3 bypass covers.-----------------Compression test is the first thing to be done when trouble shooting.-------------Looks like we have a long , long story here that should have been a short story.-------I like the compression numbers on the other bank.
 
The bypass cover allows you to look at the pistons / rings at minimum expense.---------Those gaskets are like $ 2.00 each.
 
I see that. I took them off. Rings and pistons look good. 1 head bolt broke off. It will turn in block, but is frozen in head. Being patient. Soaking with PB blaster.
 
use patience when removing head bolts.loosen a little, tighten a little,work bolts back and forth,dont force, maybe to little to late on info!
 
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