Project 1973 GlasPly 191VIP Mercruiser 165 Inline 6 MC-1 Outdrive - QUESTIONS

[goldmember165]

Hi All, just joined the forum, I read the adults only sticky and hope I provide the proper information and keep my questions simple to get the fastest help possible. I'm not new to the boating world but am new to stern drives and inboard engines.

Sorry to cram a lot into this post hopefully someone can make sense of it but my current issues are as follows: water in the oil, cracked oil pan, lack of proper shift engagement, boat struggles to get on plane (but after reading forums sounds like gunk in the fuel filters/carb which I will check)

A little back story on the boat since I picked it up: (will post as many pictures as possible)

It is a 1973 Glasply 191VIP (19.5') with the mercruiser 165 inline 6 with MC-1 outdrive...it was given to me for free from a friend because he knew it needed a lot of work (stringers/floor/seats/engine/windshield, the list goes on...) Right off the bat I had to pull the heat exchanger? (what the carb mounts to) off the engine and weld up the big crack in the water jacket that I hear is very common on these engines, l also replaced that gasket (which went well and no longer leaks water from the engine into the boat, woohoo!) I got it running by replacing the coil, plug wires, cap, rotor, points and condensor. (setting dwell and timing) Although it runs and seems to run strong, it has a very odd sound which will make sense in a minute... (if someone has a way I can send a video of it running I can show you), but I took it out on its maiden voyage anyways to make sure my bellows/transom work didn't have any leaks. I did driveway tests with muffs on and didn't have any issues there. What i found after running the engine up to normal temp under load was oil dripping from the bottom, put my hand underneath and turns out there is a crack in the oil pan !!!

I'm hoping someone previously tried to jack or hoist the motor from the bottom and dented the oil pan upwards, causing the crankshaft to hit and then eventually crack the pan. I haven't got to taking it off yet because now I have to cut my newly built floor up and remove fuel tank and hoist up the engine a little in order to be able to slide the oil pan out. I'm really hoping it has been dented in by some i*d*ot and not a crankshaft issue or something internal. Has anyone had a similar issue or heard of this kind of thing before? (I have a hard time believing its crankshaft issue since it does run good and reaches high rpms and holds it no problem)

Also, when running on the lake yesterday the boat was struggling to get on plane, like I mentioned up top (and understand it could be dirty fuel system/carb), but once it finally gets up to speed the rpm gauge was showing 6000 and didnt have gps to see how fast I was going but definitely didn't feel like 40mph. It has a mint condition quick silver LaserII prop I believe is either 21 or 23 pitch...whether that would cause that much difference or not in RPM's, I doubt it. Anyway, the prop also has a very slight, but noticeable by eye, wobble to it that appears to be the shaft that its mounted to. The gear oil that came out was disgusting and there wasn't a whole lot in there, I replaced it and filled to the proper level where it comes out the vent screw hole. Also replaced gimbal bearing and bellows.

Sorry for the long story and I know I have some work to do and can probably answer my own questions by just getting out there and getting my hands dirty but was looking for some insight and knowledge from the experienced.

To summarize my issues; cracked oil pan, water in oil, slightly wobbly prop, sluggish engine out of the hole, high rpms, poor shifting.

Thanks for any info!!!

 

[achris]

:welcome: to iboats.

I'll dissect this and deal with the issues one at a time...

Hi All, just joined the forum, I read the adults only sticky and hope I provide the proper information and keep my questions simple to get the fastest help possible. I'm not new to the boating world but am new to stern drives and inboard engines.

Sorry to cram a lot into this post hopefully someone can make sense of it but my current issues are as follows: water in the oil, cracked oil pan, lack of proper shift engagement, boat struggles to get on plane (but after reading forums sounds like gunk in the fuel filters/carb which I will check)

Water in the oil is usually a cracked engine block or manifold due to improper winterizing.

A little back story on the boat since I picked it up: (will post as many pictures as possible)

It is a 1973 Glasply 191VIP (19.5') with the mercruiser 165 inline 6 with MC-1 outdrive...it was given to me for free from a friend because he knew it needed a lot of work (stringers/floor/seats/engine/windshield, the list goes on...) Right off the bat I had to pull the heat exchanger? (what the carb mounts to) off the engine and weld up the big crack in the water jacket that I hear is very common on these engines, l also replaced that gasket (which went well and no longer leaks water from the engine into the boat, woohoo!)

Manifold (these ones are a combined intake and exhaust)... Yes, they crack when the water in them freezes during winter. That's what winterizing is, draining all the water from the engine and manifold.

I got it running by replacing the coil, plug wires, cap, rotor, points and condensor. (setting dwell and timing) Although it runs and seems to run strong, it has a very odd sound which will make sense in a minute... (if someone has a way I can send a video of it running I can show you), but I took it out on its maiden voyage anyways to make sure my bellows/transom work didn't have any leaks. I did driveway tests with muffs on and didn't have any issues there. What i found after running the engine up to normal temp under load was oil dripping from the bottom, put my hand underneath and turns out there is a crack in the oil pan !!!

I'm hoping someone previously tried to jack or hoist the motor from the bottom and dented the oil pan upwards, causing the crankshaft to hit and then eventually crack the pan. I haven't got to taking it off yet because now I have to cut my newly built floor up and remove fuel tank and hoist up the engine a little in order to be able to slide the oil pan out. I'm really hoping it has been dented in by some i*d*ot and not a crankshaft issue or something internal. Has anyone had a similar issue or heard of this kind of thing before? (I have a hard time believing its crankshaft issue since it does run good and reaches high rpms and holds it no problem)

Those engines have a pressed steel sump. They don't 'crack', but what they do do is rust out. More likely what you found is the rust hole. And you can't just 'slide the oil pan out' The engine needs to be completely removed from the boat for the sump to be removed.

Also, when running on the lake yesterday the boat was struggling to get on plane, like I mentioned up top (and understand it could be dirty fuel system/carb), but once it finally gets up to speed the rpm gauge was showing 6000 and didnt have gps to see how fast I was going but definitely didn't feel like 40mph. It has a mint condition quick silver LaserII prop I believe is either 21 or 23 pitch...whether that would cause that much difference or not in RPM's, I doubt it.

On that boat, no way is the engine reaching 6,000rpm with a 23" or 25" prop! Check the back of the tacho and make sure it's on the '6cyl' and not '4cyl' setting.

Anyway, the prop also has a very slight, but noticeable by eye, wobble to it that appears to be the shaft that its mounted to.

Not uncommon for the prop to exhibit a slight 'wobble'. Take a dial gauge and check the prop shaft itself. No more than 4 thou runout.

The gear oil that came out was disgusting and there wasn't a whole lot in there, I replaced it and filled to the proper level where it comes out the vent screw hole. Also replaced gimbal bearing and bellows.

You need to define 'disgusting'. Was it just old and black or did it have water in it?

Sorry for the long story and I know I have some work to do and can probably answer my own questions by just getting out there and getting my hands dirty but was looking for some insight and knowledge from the experienced.

To summarize my issues; cracked oil pan, water in oil, slightly wobbly prop, sluggish engine out of the hole, high rpms, poor shifting.

Thanks for any info!!!

Sluggish out of the hole backs up my 'prop too coarse' theory. That engine, that boat, prop shouldn't be any bigger than about 17", 19" absolute maximum. Get a shop tacho (maybe in the dwell meter you used to set the points) and verify the tacho. Dash tacho are almost never accurate, especially at the upper end.

Chris......

 

[goldmember165]

Hi Chris,

Thanks for the reply. So with me fixing the big outer crack in the water jacket and putting a new manifold gasket on, should that eliminate water in the oil? Would the reason I'm still seeing milky oil be because I have to flush it out over several oil changes or is it possible it's getting in another issue? After running on the lake yesterday I didn't notice a change in the level on the dip stick.

As for the crack in the oil pan, it has obvious cracks, not a rust hole and there is two adjacent from each other about 1-2" apart running about 1.5" width wise in the middle of the pan, under the ignition coil/distributor end of the engine. I have attached photos. You can also see what look like grooves or dips in the pan from the crank hitting it. When the engine is running and you push up in that problematic area, you can feel the crank hitting the pan with your fingers. It seems to most definitely be pushed up given the creases on the bottom of the pan and also the paint being chipped off specifically in the area that its hitting and has the cracks.

I was able to dissect the numbers on my prop and found out its roughly 14" diameter by 23 pitch. Also the tach on the dash was already in the 6 cylinder position. So not sure if that prop size has anything to do with the over revs on the tach or if the tach is just being glitchy or perhaps it's some other underlying issues I'm not aware of. Also thanks for the tip on the prob shaft wobble, I will check that out. If it's out much more than 4 thou how big of a job is replacing that? And would that cause cavitation and high rpm's/lack of power out of the hole?

The oil in the lower unit did potentially have some water in it to cause milkyness but mainly just old looking oil and lack thereof. It's been a while since I drained and replaced it now and can't fully remember...

Thanks for working with me on this, not too many boat mechanics in my area. I live in a small mountain town north of Whister, BC.

 

[achris]

Hi Chris,

Thanks for the reply. So with me fixing the big outer crack in the water jacket and putting a new manifold gasket on, should that eliminate water in the oil?

No. You are getting water in the oil because there is an internal crack in the engine block. The only way to fix that is a new engine block.

Would the reason I'm still seeing milky oil be because I have to flush it out over several oil changes or is it possible it's getting in another issue? After running on the lake yesterday I didn't notice a change in the level on the dip stick.

Only takes about 2 tablespoons of water to emulsify with the engine oil to look terrible. You wouldn't see that on the dipstick.

As for the crack in the oil pan, it has obvious cracks, not a rust hole and there is two adjacent from each other about 1-2" apart running about 1.5" width wise in the middle of the pan, under the ignition coil/distributor end of the engine. I have attached photos. You can also see what look like grooves or dips in the pan from the crank hitting it. When the engine is running and you push up in that problematic area, you can feel the crank hitting the pan with your fingers. It seems to most definitely be pushed up given the creases on the bottom of the pan and also the paint being chipped off specifically in the area that its hitting and has the cracks.

Yes, I looked at the photos. I think you're right and it is the crank hitting the pan. Never seen that before. No idea.

I was able to dissect the numbers on my prop and found out its roughly 14" diameter by 23 pitch. Also the tach on the dash was already in the 6 cylinder position. So not sure if that prop size has anything to do with the over revs on the tach or if the tach is just being glitchy or perhaps it's some other underlying issues I'm not aware of.

a 23" pitch prop on that boat is WAY too much. Your tacho is serious out. Check it against a know good tacho...

Also thanks for the tip on the prob shaft wobble, I will check that out. If it's out much more than 4 thou how big of a job is replacing that? And would that cause cavitation and high rpm's/lack of power out of the hole?

Lack of power out of the hole is the prop pitch being too much... And your revs aren't high, they will be low. Check the tacho, it's reading a long way high.

The oil in the lower unit did potentially have some water in it to cause milkyness but mainly just old looking oil and lack thereof. It's been a while since I drained and replaced it now and can't fully remember...

Yeah, I think you have more things to worry about (at the moment) that the drive...

Thanks for working with me on this, not too many boat mechanics in my area. I live in a small mountain town north of Whister, BC.

Not a problem...

 

[goldmember165]

Yeah unfortunately it sounds like a replacement motor is the only option if the only cause of water in the oil is an internal crack...not the news I was hoping for...especially after putting all this money and insane amount o time into the restoration...ouch. I received false information from previous owner who is a friend of mine, claiming the oil never had water in it until that exterior crack showed up and he took the manifold off to jb weld it up but then damaged the gasket when reinstalling and claimed that was the issue for water getting in, boy was he wrong. Must have cracked internally at the same time the external crack occurred over last winter and he just had no idea...well, time to sell the boat as is and hopefully get my money out of it. Engine replacement is out of my scope of work. Thanks a ton for the information and help with it all.