'84 Lund 3.0L IO engine runs, locks up, runs, locks up

[bigtoyz]

Bought an '84 lund with a 3.0L Volvo (love it) from a guy who overheated it. Plug in outdrive blew out and so didnt pump much water in. Rubber exhaust melted. Just told me it would stall. I drove it for 30+ min before it locked up at low speeds. Wouldnt turn over. Seemed like water in cyl had locked it up. 45 min later it fired right up. I had the head checked for cracks and planed. Once together, it fired right up several times. Put it in the water, it ran for about 2 minutes and locked up. 40psi oil press. It would barely crank. Pulled the plugs and that didnt change anything. (no water) Drained the block and there was water circulating. Brought it home and an hr later it fired up and ran (out of water). There has never been water in the oil. Any ideas??? Something goofy in the engine so I may rebuild it this winter just to make sure it is ready. I may not be able to put it in the water before spring river sturgeon fishing.
Im a mechanic but never had an engine stump me like this. It makes no sense. What am I missing? ANY SUGGESTIONS??????

 

[Scott Danforth]

Did you replace the raw water pump?

Burnt exhaust rubber bits mean no cooling water

 

[Bt Doctur]

what about the oil level in the drive?

 

[bigtoyz]

Hi guys, thanks for the replys. I did not blow out the exhaust. I didnt realize I would need to. Can you give me a quick explanation how to? Where would those bit be plugging?
I did not replace either water pump. I did drain the block and the exhaust and water came out of both. The one on the drive or the one on the engine?
Oil level in the drive was new. He had drained it and I filled it back up before putting it in the water.
The first time it ran for 30+ minutes and at slow speed it abruptly stopped and wouldnt crank over, 1 hr later it fired right up.
2nd time it idled for 2 minutes and again stopped instantly, would barely tuurn over, and 1 hr later fired right up.
I was wondering if the exhaust manifold got so hot it cracked and now lets water leak into the intake runner?

 

[alldodge]

what about the oil level in the drive?

As BT mentioned have you checked the drive lube?

Or pull the drive and run the motor with the drive off. Connect hose to the thermostat housing

 

[bigtoyz]

Just to make sure I understand, you are talking the lube at the bottom end of the drive by prop, 2 plugs, fill the bottom until it comes out the top, or is there anywhere else it needs lube? Also, when I had the head off there were no signs of scoring in the cylinders as if it had overheated and seized.

 

[alldodge]

Yes see if its filled to the top

 

[bigtoyz]

And, the last time it sat ideling for about 3 minutes in nuetral, still strapped on the trailer so the drive shouldnt even be moving. But it was filled with new oil.

 

[alldodge]

And, the last time it sat ideling for about 3 minutes in nuetral, still strapped on the trailer so the drive shouldnt even be moving. But it was filled with new oil.

The drive is turning inside everytime the motor is running

 

[bigtoyz]

Can you tell me where or how to access the drive oil to check it? I thought the only gear lube was down by the prop.

 

[alldodge]

Depends on which drive you have, do you know?

If its a SX look on the top of the drive for a plug which will also be a dipstick.

 

[bigtoyz]

I do not know which drive (the one pictured looks familiar) but I will check in 4 hrs when I get home. Thank you so much for the info. Will let you know.

 

[Scott Danforth]

Can you tell me where or how to access the drive oil to check it? I thought the only gear lube was down by the prop.

The whole drive is filled with oil

 

[bigtoyz]

Well guys, you know your stuff! Thank you! I have a OMC Cobra drive behind a GM 3.0. And I have NO fluid in the drive that I can see. The short dipstick came out, and with a flashlight I could see no trace of oil, even from being thrown around in there. Hopefully there is no serious damage yet. What are the chances of having this happen just as he runs the engine hot??? What type of oil goes in? 80/90? Synthetic? Im going to try once last time in the water before its parked.
Scott also talked about replacing the water pump (Engine or the lower unit?) and blowing the old rubber bits out of where to let water in?
Thank you again for the help.

 

[Scott Danforth]

I would pull the drive for winter so you can go thru it. the transmission on the AQ drives is at the top. if you ran it dry, you probably did some damage to the bearings and the gears. those drives take just shy of 3 quarts of fluid

 

[bigtoyz]

WHat type of fluid? I am thinking I will fill it and run it some to make sure it doesnt have any other issues and that this was the problem. Are parts still avaible for these? I read Volvo Penta aregetting scarce.

 

[alldodge]

It will be VP 80w90 gear lube. Before even trying that, remove drive and have it looked at. For the most part in my opinion, the drive needs to be replaced ir full rebuild

 

[Scott Danforth]

you can find parts for them. however best to look used on fleabay and CL. new your looking at about $2500 for the transmission

if you have a single prop, used to be SAE 30. however I would run SAE 80W-90 synthetic marine gear lube.

 

[Scott Danforth]

being a 1984, you should have the 10-spline input shaft and you will need shims to rebuild the gear box (the later ones use crush sleeves)

 

[bigtoyz]

Is there a good manual online or that a guy can purchase to go through the trans?