| Author |
Message |
    
Tom G.
Member
Username: tomfg
Post Number: 5
Registered: 01-2013
| | Posted on Thursday, January 31, 2013 - 06:36 pm: | 
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Tomorrow may be the day I hear my GRAY run. I did pour a tiny bit of gas in the sparkplug hole before I called it quits today, and it fired twice, so I'm hopeful. My gas sediment bulb gasket was weeping some, and I haven't mangaged to get the water pump to take prime. I put the coolant tank on a stool so it was elevated above the engine, and cranked the engine over with the plug out for quite a while, but never did get fluid to come out of the engine return line. Perhaps it's air bound? Maybe I can loosen a plug on the pump to get the air out. I did get the all the air out of the suction line to the pump though. BTW, the skid is screwed down to the workbench. Oh yeah, still have to make or come up with a muffler..... the two pops from the engine today were rather loud.
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J.B. Castagnos
Senior Member
Username: jb_castagnos
Post Number: 753
Registered: 07-2002
| | Posted on Thursday, January 31, 2013 - 10:53 pm: |
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It looks good Tom. Your tank may be a little low, fuel will flow slow when below half. The water pump only pumps in one direction, be sure you're cranking the right way. |
Tom G.
Member
Username: tomfg
Post Number: 6
Registered: 01-2013
| | Posted on Thursday, January 31, 2013 - 11:14 pm: |
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J.B., I was under the impression that the engine will run in either direction, and that the water pump doesn't care which way the crankshaft is turning, as it's a piston pump, and only knows "up and down" ?
I have the bottom of the fuel tank even with the top of the fuel bowl. Not a lot of head pressure I know, but I wasn't sure how well the need / seat works. Guess I can always raise it if needed.
Thanks, Tom |
J.B. Castagnos
Senior Member
Username: jb_castagnos
Post Number: 754
Registered: 07-2002
| | Posted on Friday, February 01, 2013 - 06:39 am: |
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Tom, I didn't look close enough, most of the Grays had the gear pump on the timer shaft, the piston pump doesn't care about direction. |
Tom G.
Member
Username: tomfg
Post Number: 7
Registered: 01-2013
| | Posted on Friday, February 01, 2013 - 08:34 am: |
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J.B., thanks for clearing up the water pump rotation. This is my first marine engine, but have played around with stationary farm engines.
Regarding the GRAY's with gear pumps- were these the earlier engines? Mine is a 1924. |
J.B. Castagnos
Senior Member
Username: jb_castagnos
Post Number: 755
Registered: 07-2002
| | Posted on Friday, February 01, 2013 - 08:36 pm: |
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Here's a couple of links to the "sandsuckers"
http://www.oldmarineengine.com/discus/messages/1/6090.html#POST8588
http://www.oldmarineengine.com/discus/messages/1/1299.html#POST2402 |
miro forest
Senior Member
Username: miro
Post Number: 662
Registered: 11-2001
| | Posted on Friday, February 01, 2013 - 11:18 pm: |
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Tom, do you have a check valve after your carb?
The Gray's usually had one. If you don't have one, it might not start or run well.
Maybe Richard D, can advise on this model - did it, or should it have a check valve.
miro |
miro forest
Senior Member
Username: miro
Post Number: 663
Registered: 11-2001
| | Posted on Friday, February 01, 2013 - 11:23 pm: |
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Taking a closer look at the engine, it looks to have a decompression petcock half way up the side of the cylinder.
When starting you open the valve, thus relieving some, but not all of the compression, making the engine easier to start. Once it's running, you close it.
But Tom, you'll have to sort out the issue of gas tank height for sure, before you try getting the engine to run.
miro
miro |
RichardDurgee
Senior Member
Username: richarddurgee
Post Number: 2970
Registered: 11-2001
| | Posted on Saturday, February 02, 2013 - 01:53 am: |
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*
The R and S model engines were two port design and require an inlet valve.
The U model engines were 3 port design and had the anti backfire screen in the port and do not require an intake valve !
This Model U information shows the 3 port dersign but also shows the rotary water pump, later engines used piston pumps !
* |
Tom G.
Member
Username: tomfg
Post Number: 8
Registered: 01-2013
| | Posted on Saturday, February 02, 2013 - 09:45 am: |
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Thank you all for your input and replies. I did not try my first start the GRAY yesterday, as it was -28 F. when I got up, so didn't even bother to build a fire. Only -16 this morning, so I may get out there yet!
Regarding the de-compression petcock- my engine had the port for one, so I added one.
Glad to know I don't need a check valve on the carburator.
Thanks, Tom |
