Alpha 1 overheated badly

[viper1]

Well the islander out drive has been more of a disappointment then I was hoping. It was running hot. So changed motor thermostat. Bellows were cracked so removed every thing and replaces all bellows, the water hose in there and Gimble bearing was good. Decided to redo the impeller so tor the lower off and it was really shot. It had been overheated and the impeller was melted and case was shot. So replaced them. Plus the oil seal. Before assembling I looked into the top section and the rubber seals at the entrance of were lower shaft goes was melted and distorted too.
So thought about replacing seals, but the one looks like a teardown to insert from the inside. So my question is, isn't there a good chance since it was so over heated that bearings and all rubber in side is gone also. At least that's what my reasoning seems to be. Wondering if a used alpha one out drive with my new impeller wouldn't be better.
Also would size of motor dictate the type of Alpha one I need? Mine in a 1989 mercruiser with an Alpha one but not gen II. Would one off a v8 or v6 fit mine with the 190? Seems drive should be same. Also whats required to change an alpha 1 to a gen II?

 

[HT32BSX115]

Howdy,


Well, I am not sure what engine you have........ A 190? Is that a 470 (4cyl aluminum block, + Ford 460 head?)

If so, you'll need a drive that came off a 470.
One of the '470 guys should jump right in here, but if I am not mistaken, the 470 used a particular ratio unique to the 470

A drive from a V-8 would likely be a 1.50:1 and would probably be a bit high.

You might also consider an SEI drive if yours is not usable, They can sell you the right (new) drive with a 3 year warranty.

Post your engine package model and serial number. Everything Mercruiser is based on serial number range.

Oh, AND, going from an Alpha to a GENII may require a different gimbal mount, and maybe a different flywheel housing. I don't think you can just swap drives and be done with it.

Having said all that, just overheating the engine didn't necessarily damage the drive.


Regards,


Rick

 

[viper1]

Its a 190 4 cyl straight. Looks like a chevy mercruiser I'll need to know were to find the serial number for package. As the plate on side of engine is blank. But i'll try to look. Havent got the coin for a new or rebuilt. I'll need to buy use. Hope later to buy a rebuilt or do it myself. If i get a used one could make a good winter project to rebuild this one.

 

[HT32BSX115]

Yeah. That's the (infamous) 470 engine (NOT Chevy! )

The block was designed by Mercury and it has a Ford 460 cast iron head

There's a great many people with them here on iBoats and most are very familiar with what you can, cannot and should do to keep it running great.

There's some very specific things you should watch (temp being one of them!)

Anyway, someone will jump right in here with the "stuff" you need. In the mean time, it'll be good to post the serial number. THere were some things that are different with different series.......

If you overheated the engine there is a risk of a failed head gasket warped block and/or head.

Also, if you ran it long enough with no water flow in the exhaust system, it's likely you cooked all the rubber parts in the exhaust. You probably didn't severely damage the drive other than replacing the raw water pump, housing and other plastic components. If you have an oil or power steering cooler, there's probably pump fragments in them. If not, those fragments went into the heat exchanger. You'll need to completely flush the cooling system.

 

[viper1]

Well here is where i am now. I originally started it and was letting it heat up to check carb after changing Plugs Cap and rotor. Engine stated heating up so I shut it down, I didn't over heat it much at all. So I changed the Thermostat in engine. Was going to do the impeller to be sure it was good. But seen the Bellows were cracked and dried. So pulled out drive and bell housing. I changed all three bellows and water hose in there and the shift cable and ends. Split the case and changed that bad Impeller. It was also pretty low on gear lube. Before reassembling the out drive I flipped top over and both seals in upper looked deformed and melted. So found another upper for 30.00 a guy had left. He needed lower and to lazy to change whole out drive so I lucked in. The seals and all look good in it. But didn't like the looks of the water passage housing. So took mine out of the other and got a gasket to night for it. Flushed out cooling system before putting in new thermostat. So I'm ready to assemble lower to upper and install. I believe only the out drive was over heated. I think probably because there wasn't enough gear lube. Hoping the lower is in better shape. But without tearing it down I don't know any way to tell.
Now don't mean to sound like a boat mechanic. But i was an auto mechanic. So i have some experience to form opinion.
Also figured Id take it to Berlin Lake to run and check out before taking It to Lake Erie. But when I fired her up the motor sounded real good, started easily but might need carb adjusted.
Also where is the serial number you need located? I got this off the out drive. 1.98r 08858350 Not sure if thats it or not.

 

[flipbro]

Usually the upper part of leg suffers most when low drive oil conditions occur. Pop the top cover and inspect the condition of bearing and gears.

 

[Eric 3.7LX Alpha 1]

The gear ratio is in the upper half of the drive. Your engine calls for a 1.84:1 ratio. Do yo know what the new upper's gear is?

You can run the engine with the drive off, stick the garden hose in the water inlet in the bellhousing and your good to go.

 

[viper1]

Well cant find it on the upper i just got. But the one i had is 1.98r. It looked like it was redone or new before this. Drive shaft and universals look new too. I wanted to tear it apart to look. But seems like many special tools needed. The spanner wrench it self is 80.00. Could i drive it off or is a spanner necessary? Does the drife shaft and gears have to be removed to pull the upper out? The unit i got come from a boat with same engine and same year. But i haven't found the gear ratio. The two seals i believe is bad are the two in bottom of upper. Looks like one is inside and one out side.

 

[NHGuy]

1.98 and 1.8 are 10% apart. so you might need a taller prop if you use that upper. I'm going to look up the "r", hopefully it's not reverse ie. counter rotating. If it is I suppose you could cannibalize the water pocket.

 

[Eric 3.7LX Alpha 1]

The two seals your referring to at the bottom of the upper unit... The bottom one pops out from the outside, just stick a screwdriver or seal puller and pop it out. and tap the new one in there with an appropriate sized socket.

The upper seal goes in from the inside. You'd have to pull the gears out to replace that one.

Did the upper come with a drive shaft and uni's on it? There's a stamped letter on the driveshaft which signifies the ratio... so long as nothing has been changed with it.

see the chart right side of page for the letter and ratio:

 

[HT32BSX115]

I think probably because there wasn't enough gear lube. Hoping the lower is in better shape. But without tearing it down I don't know any way to tell.

If the oil was 'low" and the drive was operated long enough for it to get hot (which is no time at all) BOTH the upper and lower ARE damaged. There really is no such thing as running a drive "LOW" on oil. LOW=damage.

This WILL require a rebuild of both since they both share the same oil and any metal debris from running it low will circulate top and bottom. As indicated above, you can use a ratio slightly lower but you'll need a 'taller" prop (I.E. if you had a 19p prop with the 1.84:1 drive, it might be ok with a 21p prop using a 1.98:1 drive etc.) You'll just have to experiment.

 

[viper1]

Yes the new used one came with yolk and drive shafts , universals. I was looking at the diagram on these. Seems if you remove the Retaining nut on the horizontal drive line the gears and all should pull out for inspection. Then the vertical can be removed. Can a person do this and inspect then reassemble if ok? If the gears and shim packs arent removed maybe just new oil seals? Also if not can I remove and have redone then assemble them?

 

[viper1]

Ok well assembled and ready to set trim limit, trim sensor, shift cable end inside dog house. Then I'll give it a test start. Keeping fingers crossed no damage to lower unit. But i took a magnet to the gear lube I drained. No metal at all i can find. And the lube was like new. Just not enough. Wondering if he drained and pumped some in before selling. But will know one way or the other in the next couple days. Also I noticed the trim on this was set to about 3" and at that the lower unit is low in back. I believe the setting to be 6.5 according to the book. Still need to get a bolt for the little anoid like trim on back of out drive. Old one was not very good.