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1976 Ford 302 Lower Re-build

I got the new Arco starter in, and it worked. So, I turned the engine over without the plugs to blow out any excess gas that may still be in the cylinders. I gapped the standard plugs at .035 and put them all back in and attached the plug wires, making sure to get the right wire on the right cylinder.
It was getting dark but decided to see if it would start. I pumped the bulb to get gas into the fuel filter, fuel pump, fuel line, and carb reservoir, but it only took a few pumps until I got resistance, so it probably didn't get very far, but erred on the side of not flooding it, so I tried turning it over. It didn't start or hit at all, and there was still that hitch, like a sticky valve or something, causing the crank to slow at one point in the cycle. I just tried it about five times and was dark enough that I decided to wait until tomorrow.
That hitch is very concerning. It doesn't seem that it was from gas in a cylinder, which is what I thought it would be, as it had a week to evaporate, and I turned it over without the plugs in. The plugs I put in were slightly used but not fowled.
Before it had quit starting, I had just checked cylinders 8, 7 and 6, turning it over with the plug out, and the hitch was still there, so I could check the rest of the cylinders.
I don't know that I have gas to the carb yet. Probably not, with the new fuel pump, and I took the fuel filter off for access, so there was not fuel in any of those lines or the pump.
I did want to do some fuel tests but need it running.
I guess I will try staring it again and make sure gas is getting to the carb and not worry about the hitch. If it still doesn't start, go through the rest of the cylinders taking each plug out and turning it over to find which cylinder is causing it. Or should I be more concerned with the hitch?
 
The first thing I did was I took off the fuel hose at the carb, and fuel gushed out, so it had and has gas. I also took apart the linkage and pumped the throttle and there was gas coming out of the jets in the venturi. So, I turned it over a few times with no hit and still that hitch.
I started taking the spark plugs out at number one, and it had a spark and was still the hitch. I went to number two, and it had a spark and NO hitch. I did a compression test on that cylinder, and it came out to 145, which is not bad. They were all between 150 and 160 before. The engine is just nicely broken in after it's overhaul, with only about 30 hours on it. I just turned it over a few times without the plug to clear out any gas that may be in there. I put the plug back in and still had the hitch and never once had any hit.
Got gas, got spark, timing set where it was before. Not sure what I am missing here. Not sure what else may have changed since I re-installed the intake manifold. I was careful not to get anything in the orifices when I cleaned off the heads, I used a sheet of tinfoil to cover the area to clean off the old gaskets and put paper towels in the other holes.
Okay, I went back out to check the timing with a timing light, and it looked pretty good. My timing light is not very bright but looked like it was near my mark. I did twist the distributer around a few degrees in both directions, but still no hit.
Perhaps the new fuel pump is too strong and is flooding it again. The instructions say not over 6.5 lbs. But it needs to be running to check the pressure. And it did the same thing with the old fuel pump, which was meager on the volume.
Is there anything else I can do with the #2 cylinder? Is there anything else I can test?
 
So, I went out to try starting it again after two days, I didn't touch a thing, except to turn the ignition. I tried about 5 times for 20 seconds and I may have gotten one little hit on the second try with the persistent hitch. I decided to take the #2 plug out and try starting it without the plug in, maybe something would fly out or something, and the hitch was STILL THERE! Although I did get one loud hit without the spark plug on number 2. I thought I found the #2 plug without the hitch on Sunday, so now I'm a bit confused. I took out the other plugs of the cylinders that I hadn't yet checked, and they all had spark and the hitch. I may have gotten another small hit on one of those.
I am pretty sure that it turned over smoothly without any plugs in, and figured taking one out at a time, that I would find the problem.
To clarify the Hitch, it is a slowing of the crank at one point on the cycle.
So what is next? Check compression on all cylinders, I guess.
Any other ideas?
 
Ok, long thread, help me understand....

1) Oil leak so you pulled manifold off to replace the gaskets. Engine ran but with what appears to be a fuel delivery issue. Yes/No?

2) Reinstalled manifold but now doesn't pop/start/run. Yes/No?

3) Starter failed thru all this, new starter installed. Yes/No?

4) Engine sounds as if it binds at a particular point of rotation while cranking. Yes/No?

5) Same symptoms as #4 above with all 8 plugs removed. Yes/No?

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If #1 & 2 are Yes go back & verify distributor is timed correctly. Just because you marked the distributor body to manifold doesn't mean the shaft is timed correctly.

#3, Are you sure you have the correct rotation starter & not reverse rotation. Watch crankshaft pulley while cranking to verify.

#4, Again, watch CRANKSHAFT rotation while cranking & see if it's in the same spot each time it binds.

If #4 is Yes the binding may be in the intermediate housing or input (ball gear shaft) shaft bearing of upper housing. ***

If #4 is No the binding may be in the vertical shaft of upper housing or in lower housing because they are after the gear reduction. ***

Note *** you can pull the drive to isolate it but intermediate will still be connected to crankshaft. I have seen 1 intermediate eat the bearings & bring a 351 to a no crank condition. Check intermediate, upper & lower unit oil for proper quantity/condition.
 
Thanks for your reply.
#1 is yes, it was running well before the intake manifold reinstall, with a problem at high rpms, likely fuel. I did not turn the engine between when I took the distributer off and put it back on. I did try to verify the timing with a timing light and it looked probably okay, but may have to verify it at night, when I can see the timing light better.
#2 is a yes. I reinstalled the intake manifold, taking out the distributer, the thermostat housing, and carb; and I have gotten nothing except a few meager pops. In the meantime, I also changed-out the fuel pump.
#3 Yes, the starter failed while I was trying to diagnose the problem of not starting. While waiting for the new starter, I also changed the questionable fuel pump.
#4 Yes, the engine binds at a very regular point in the cycle. I can see the alternator almost stop at a point, and I can see that it is turning clockwise, which is the correct rotation of the motor. I never considered that it may be from the outdrive itself. In fact, through some of these tests, I did not have the water on in the outdrive, as it wasn't starting anyway and I was working on taking sparkplugs out and such, and figured if it did start, that I would shut it down right away. In California, we tend to be very conscious of wasting water. Maybe this is a variable in my testing adding to the problem/confusion.
#5, the only no. It seemed to spin freely with all the plugs out, but would probably be expected to with the lack of resistance from no compression,
The only variables from the intake manifold reinstall would be possible vacuum leak, timing, spark plug wiring, carburation and then the fuel pump reinstall and the fuel filter and hoses, although the same problem was present before the fuel pump reinstall.
Going forward, hook it up to the water and try to start it again, check the fuel volume and pressure by just cranking it, and see what it looks like, check the timing at night and try starting it adjusting the distributer, and write-up my results.
 
If #1 & 2 are Yes go back & verify distributor is timed correctly. Just because you marked the distributor body to manifold doesn't mean the shaft is timed correctly.

I think that the distributor shaft was turned while out (or engine crankshaft turned for some reason) so while you have the distributor body marked & reinstalled at the same approximate mark your timing is way off. Verify timing & wires correct at each cap terminal & spark plug.
 
Right On Mr. Droid! You were exactly right!
Problem solved. The timing was about 70 degrees off! Running normal now! I thought I didn't move the engine while I reinstalled the intake manifold, because I knew that the distributer could go into any slot, but somehow I screwed it up. I got the timing set for 10 degrees before tdc, it is purring like a kitten and I will take it out this weekend and see if the new fuel pump has solved the problem on the high end.
 
I took it out today, and the good news is the fuel situation is handled with the new fuel pump. I got up to full throttle at 4100 rpm and up to 39 mph (34 knots) and kept it up for about 15 minutes with no problems. The engine ran great! Started right up!
I decided to take it out of the breakwater and practice piloting using my chart-plotter with waypoints and went to some close by fishing spots just to see how easy/ hard it is, and it is not easy. In the process of puttering around at 2000 -2500 rpm, I LOST FORWARD GEAR!
I was about a mile from the harbor, and about three miles from the launch. I tried to make it back in reverse, but I was also taking on some water, and about half-way back to the breakwater, my engine shorted out. So, I had to call up BoatUS to bail me out. I had drifted into the harbor while I waited for them.
So, now I have two lower rebuilds, and my season is over. That is three times I've lost forward gear - the two other times were broken clutch springs, and this had the same characteristics. Just like it slipped into neutral and engine revved.
I didn't do any hole-shots, just gradiently raised the throttle. And when it happened, I wasn't doing anything questionable.
Maybe I should stick with the 16-pitch prop. Anything else I should tone down? It has the standard plugs.
After I took it out of the water, I was hoping to find the leak, with the water in the boat. It wasn't leaking through the bellows, but maybe there is a leak in the bottom connection of the bellows/transom - seemed to be some drip there, but everything was wet and was hard to tell. It was a lot of water, and neither of my bilge pumps were functional. One had a bad connection to the hose. The other seemed to have shorted out. I am going to put a different kind of pump in. And re-seal the bellows - maybe a new one. And of course, the lower rebuild.
 
Neal Franson said:
I took it out today, and the good news is the fuel situation is handled with the new fuel pump. I got up to full throttle at 4100 rpm and up to 39 mph (34 knots) and kept it up for about 15 minutes with no problems. The engine ran great! Started right up!
I decided to take it out of the breakwater and practice piloting using my chart-plotter with waypoints and went to some close by fishing spots just to see how easy/ hard it is, and it is not easy. In the process of puttering around at 2000 -2500 rpm, I LOST FORWARD GEAR!
I was about a mile from the harbor, and about three miles from the launch. I tried to make it back in reverse, but I was also taking on some water, and about half-way back to the breakwater, my engine shorted out. So, I had to call up BoatUS to bail me out. I had drifted into the harbor while I waited for them.
So, now I have two lower rebuilds, and my season is over. That is three times I've lost forward gear - the two other times were broken clutch springs, and this had the same characteristics. Just like it slipped into neutral and engine revved.
I didn't do any hole-shots, just gradiently raised the throttle. And when it happened, I wasn't doing anything questionable.
Maybe I should stick with the 16-pitch prop. Anything else I should tone down? It has the standard plugs.
After I took it out of the water, I was hoping to find the leak, with the water in the boat. It wasn't leaking through the bellows, but maybe there is a leak in the bottom connection of the bellows/transom - seemed to be some drip there, but everything was wet and was hard to tell. It was a lot of water, and neither of my bilge pumps were functional. One had a bad connection to the hose. The other seemed to have shorted out. I am going to put a different kind of pump in. And re-seal the bellows - maybe a new one. And of course, the lower rebuild.
Click to expand...
 
Neil,
I've been thinking about your appetite for FWD gear springs & related....

These things normally break from shifting at too high an RPM. Obviously not your issue as you are cruising around aimlessly breaking things.

Look at the parts catalog for your drive upper housing. Doesn’t matter if tall or short profile but I do believe yours is short profile from the picture.

See items #73 (or 91 & 92 for a 4 cylinder).... these are ground or continuity springs. I see in your picture you have the bonding jumper from the left trunion to the cap in place. A poor ground can cause the drive to shift out & back into gear. Maybe you need to verify the spring is there. I have no idea why there are different spring types depending on engine size. Old drives all used the #91 & 92 type.
 
Wow! Droid, you sure are a wealth of esoteric knowledge! I kind of remember this spring when I overhauled the upper a year or two ago, but not absolutely sure. I wasn't planning on opening up the drive that is on there until I get my other lower overhauled, as I already have too many parts rolling around my garage.
So, I probably won't know for a while but will remember to check.
I will get to the original lower overhaul soon.
I will try to restrain myself from cruising around aimlessly breaking things! Keep thinking of me!
I am selling my SS 17-pitch prop, a probable culprit, on Ebay; and a few other things:
www.ebay.com

Items for sale by nefra4847 | eBay

Shop eBay for great deals from nefra4847!
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So, now I am getting gun shy. I've had 3 lower failures, two with broken forward clutch springs, and probably the third, as well. The first two I was running the standard 14 x 16 pitch prop and the last was a 14 x 17. I have the 14 x 16 that I was going to go back to and am selling the 14 x 17.
I have strived for and have not achieved reliability with almost all new parts and re-builds. I would rather it be functional than fast. And I don't want another lower rebuild.
Should I maybe go to a 14 x 14? The boat is pretty heavy but did get to 40 mph on the 14x17.
 
17 is SST cupped stainless? Then its equal to 18 aluminum.
16 aluminum should give you approximately a 400 RPM bump.
 
IDK.
There were lots of OMCs put in 24' boats with no problems (well no problems like yours). All the way yo to 235 HP (plus some 245s but they had thru hull exhaust, probably go fast stuff).
 
Yeah, I know, that is what has me perplexed. So, that kind of leaves my overhaul as suspect.
Just a quick recap:
The first time with my original lower and the 16 pitch, it blew out after about two minutes at FOT, after working up to it slowly. The clutch spring was broken and the snap ring to the forward gear had popped off of the hub assembly. I rebuilt it, but didn't take out the forward coil or bearing, so couldn't re-shim it, and I didn't notice, but the clutch hub was probably a bit worn on the edged holding the snap ring, allowing the next catastrophe.
So, the second time with the 16 pitch prop, I was working up to full rpm, and at 3500 I lost another clutch spring and found the same snap ring laying there, at the bottom of the lower, and I realized the clutch hub had lost its edge, allowing the snap ring to pop off, probably after the clutch spring broke, or not.
So, then a bought another used lower, hoping to save some time. It was also off of a 190 hp Ford 302, which was working, but the previous owner didn't feel the boat was worth saving and trashed the boat and kept the parts. It also came with the 17 pitch stainless steel prop. On the trials, with that prop, I did work up to full throttle, which maxed at only about 4100 rpm, and maintained it for about 15 minutes and then was just puttering around at about 2500 rpm and lost forward gear again - very similar but I have not, as yet, opened it up to verify what exactly broke but am assuming it is much the same scenario.
So, there is just one time that my mechanical abilities or decisions influenced a breakdown, the second time. And that is why I will be sure to remove those difficult parts and get it shimmed as best I can. I also got a new/used hub assembly.
The two other times were with operational older drives that broke. Once with a 16 and one with the 17 that the new lower came with.
In all cases they all had brand new Type C lower gear oil.
In no cases was I shifting. Seems I just maxed out the stress on the clutch spring, it broke and caused extra pressure on the snap ring, so it popped off. Or the other way around, the snap ring popped off and caused the clutch spring to snap. Not sure - what do you think?
It would probably be a safe solution to get a 14 pitch prop, to keep the stain off of an older 50 year old lower drive.
 
I assume you haven't yet checked the continuity spring?
I have a NOS Michigan 14X14 prop still in box. It's had about 10 min water test on friend's boat, RPMs too high. It could use a new home.... doesn't fit mine, I'd have pistons flying like projectiles.
 
Yes, haven't checked the spring. I am pretty sure it is in there. The outdrive is still mounted to the boat.
Let me know how much you want for the prop with shipping. They are about 8 pounds, I believe. I can't get it for a while.
Do you think the clutch spring broke first, or the snap ring popped off first?
 
Believe it or not, I've never experienced a failure, just routine maintenance. Maybe it will be obvious when you disect it.
I'll look into the prop cost & let you know.
 
I have been waiting for some needed tools for my lower re-build, so I got started by taking off the broken outdrive and moved it into my garage and then started filling the hull with some water to find my leak, and it is leaking towards the bottom of the connection of the rubber bellows to the transom. I had put in slightly larger screws, as some of the screw holes were becoming stripped - it is just a plywood transom clad in fiberglass. I used a really good sealant:

Marine Adhesive Sealant 4000/4200 Fast Cure UV (White) - Semi-Permanent, Flexible Bonding and Sealing - UV Resistant, Above & Below Waterline​

So not sure what I did wrong there. I cleaned it up pretty well. The transom seal plate is there, but it is the same color as the rubber, so you can't see it.
I guess I just redo it - use a lot of goop on the bottom. Any suggestions?
Outdrive.jpg
 
I finally got around to pulling out the forward coil and the bearing from my original drive, which anyone who has worked on these esoteric drives knows that you have to make most of the tools that are not available anymore. I started with a cheap slide hammer from Harbor freight and highly modified it to get it to work, which I won't go into the details of, but after about six different set-ups, the coil and bearing are out. They appear to be in good shape, and I put an ohm meter on both of the coils, and they are right at 6.0, which is good.
I do have a question on the outdrive that I took off of the boat from the last disaster. The picture (didn't come through) shows an exhaust leak, blackness around the exhaust housing seal towards the front, where the upper and lower drive meet. The gasket was new, and I put a lot of marine grease on it and thought I got it on straight. Any thoughts on how to avoid this?
 
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By "the gasket was new" are you referring to the 6" diameter round exhaust seal?

The correct way to install that is "open" side up onto the bottom of the exhaust housing. That way there is a slight taper downward so lower unit will slide onto it.

It is possible to install it 180deg opposite but then it can get damaged as you lift lower unit into place.
 
Okay, this is where I could use any help on the shimming from anyone who has opened up their lower. Not having the shimming gauge #314718, being unavailable on this website, the manual says to set the bearing and bearing cup on top of the forward hub, and it says to put the shimming gauge approximately where the caliper is in the following picture. And to measure with a feeler gauge the distance between the gauge and the cup (see red arrow pointing down), and it doesn't appear that there is any space there, and that it is just level from the cup to the bearing. The cup is on the outside, the bearing is next, and on the inside is the top of the forward hub. These all three seem perfectly level. There was a small shim in there before, which was damaged in pulling the bearing, probably an .002, and I have an .002 that I can replace it with, as it says to use at least on shim, but not more than 2, and they come in different thicknesses. Now I don't k now if the length of the shimming gauge has any effect on the calculation, but the red arrow pointing left is at about 71mm, or 2.8 inches. So, my guess is just to shim it with the new .002. The picture in the manual shows they are about level, but a little space between the outer cup, and putting a feeler gauge there to make up the difference.
shimming3.jpg
 
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