TOPIC: '67 80Hp Running again Update !?

Ok so I got her back on the water again and so far so good, the nut seems to be holding!



So now I just have to wait for new wheel bearings to come in. Apparently the grease and seal weren't keeping the brackish water out. Heard a really bad creaking noise driving home and sure enough the inner bearing set completely disintegrated! Luckily I only live 5 minutes from the ramp. So now a new set is on order. Darn things only lasted 4 years! Other bad part is the leaf springs appear to be rusting out already also! I guess I needed a complete dip tank of POR 15! Probably going to need a whole new trailer pretty soon.

Bob

Ok so I got her out on the water today but I think there's a cooling problem. I ran her on a hose before we went, water coming out of the exhaust and from the lower by the prop but I didn't see any coming from the side of the lower unit. Memory is failing is there a tell tale on the '67 80 hp lowers, I want to say there isn't.

Anyone?

Also borrowed the laser thermometer from work and the flywheel is at 91 degrees, the right side head (1&3)are at 140 degrees and the left side head (2&4) were 124 degrees. So the other question is what should they be reading?

I'm assuming the flywheel isn't a problem now since it's only at 91 degrees.

Bob

On my 1965 75 hp there is no telltale.

No telltale on 66 100 HP either. Just steam spit for the most part.

The temperature according to my manual (1966 Johnson 100 HP) needs to be between 125 degrees and 163 degrees after running 5 minutes at 3000 rpms. If it doesn't reach the 125 the thermostat is stuck open, if it goes past the the 163, then cooling is not functioning properly.

I know you area all far more technical than I, but I I had to review all this recently, so I thought I would share.

I would think you wouldn't want temperatures above 125 degrees, especially in the salt.

V4's tend to run a bit hotter on the Starboard bank, and here's some good info about that, including ideas for adding a telltale which might solve 2 problems at the same time:

forums.iboats.com/forum/engine-repair-and-maintenance/engine-frequently-asked-questions-faq/228380-johnson-evinrude-adding-a-tell-tale

If the problem continues you might pull the thermostat housing cover and inspect the springs/check valves to make sure they're all where they're supposed to be. You could also pull the Stbd hose off the cyl head and check for restricted water flow.

When you're underway, the poppet valve should open and lots of water/exhaust flow out the exhaust relief hole. What are the head temperatures after a higher-speed run, or are you just checking at idle on the flusher?

You won't have enough backpressure out of the water to get a lot of water discharging out the exhaust relief or other places where you think it might go. But it'll definitely go down & out the outlet at the back of the lower unit.

HTH.........ed

Jimmy, Thanks appreciate it, so I'm not going crazy!

Dave, Thanks pretty much goes with what I saw then.

Ed, Thanks for the link , I think I'll have to do that. The temps I took were after about a 3/4 throttle run for about 10-15 minutes.

Bob

Ran her again yesterday and she seems to be running ok, nothing above 140 on the starboard and 128 on the port bank but I will be putting in that tell tale. It actually looks like there's a screw in the "boss" mentioned in the iboats article, so it may be real easy.

Anyway she did have a starting problem a couple times, the darn gear stayed engaged to the flywheel again. I had taken it apart last year and re-lubed it too! Starter didn't like that of course and I had to free up the gear. The starter also didn't like the duty cycle either as it was getting real hot.

I guess the question is can you have too big a battery on these? The one that I'm using is a marine one with 720 cranking amps. Too much?

Bob

Battery is not the problem. Problem is the starter. Starter should drop out once the engine RPMs are higher than the starter and the bendix winds back down. Most likely you need a starter (might want to change the solenoid first, just in case it is sticking...

Agreed. I run 2 batteries on mine. Generally, the more battery the better. Probably easiest to replace the whole starter. Problems that may cause the starter sticking problem as follows: Worn out bendix spring, worn out bushings on the starter gear, or the shaft gouged from the gear bushings. Also, if the flywheel gear is worn out, it will tend to grab and keep the starter gear.

Usually if the solenoid fails, it will just stop working, but its entirely possible for it to stick while operating,, and make the starter stick.

At least these motors are serviceable!

You probably should check the starter gear to flywheel tooth clearance. There should be a minimum of .010 inch clearance or more. I've attached a procedure for setting a geared Chevrolet starter.
The process is the same for most all starters.
The exact clearance isn't critical, just so there is some clearance. I recently completed a Scott Atwater 60 HP rebuild with donor parts from a number of motors and I ended up shimming the starter.
The first photo shows how I wind the bendix drive out and hold it out with a piece of wood. Then I bolt the starter in position. The next photo shows the clearance being checked with a .025 wire.

Don

we have a used one, however on a starter i'd go new if i could find one that wasn't really pricey

Thanks for all the inputs guys. I'm going to take the starter out and check for any end play and make sure the bushings are good. I use to rebuild starters and alternators back in high school so this one shouldn't be bad to do. A new on would be great but like John says if I can find one it won't be cheap!

I forgot about the clearance to the flywheel starter gear so thanks Don, I'll check that for sure.

Bob