mlbinseattle
Petty Officer 2nd Class
- Joined
- Aug 1, 2015
- Messages
- 100
First time boat owner, here. It's a '76 850. I bought the boat a few months back and have been working on it ever since. I didn't know jack squat about 2 cycles, so I had to learn along the way. I had to fight just to get it started, and it ran pretty sad. It wouldn't get over 5mph without stuttering before stalling, and it had a terrible miss. Gaskets and bottom crank cap seals were shot. Had to replace the bottom crank cap seals, transfer port cover gaskets, exhaust plate/outer jacket/inner jacket gaskets (that was a nightmare), and cylinder cover gasket. New set of plugs, and both carbs were rebuilt. I also replaced the water pump. Before all the work, and when I was able to get it running, it ran hot. Pee-hole stream was scalding, and you couldn't lay hands on the engine. It was extremely difficult to get it restarted.
I finally performed the link/sync on it, today. Amazing how these engines run when the carbs and timing are set just right. It runs great and cranks right up. Actually, it cranks pretty easy for the first start of the day. The hole shot is pretty awesome. It gets right up there. It runs much cooler, too. The pee-hole stream is warm (not scalding, anymore), and you can actually lay hands on the engine without getting burnt. My wife and I had it out on Lake Washington here in Seattle, today, and this is the first time we were able to actually enjoy the boat. I couldn't have gotten this far without input from this forum, and I really do appreciate all the help everyone has given me so far.
Now, here comes the questions:
1) After replacing the impeller, it appeared to have a steady, strong stream during idle. Now, at idle, it appears like a weak drip until I increase the RPM's, and then it comes out in a stream although not like it used to right after replacing the impeller. Is this normal? I can blow back through the pee-hole, and I can hear it gurgling down in the lower unit around the impeller, so I know there aren't any blockages. Additionally, it doesn't run hot. I can put it in gear and turn the prop by hand, and the sound of the new impeller sounds the same now as when it did right after replacement. So, that tells me the impeller is still good and turning, in my opinion. I know one isn't absolutely positive about anything unless it's inspected. I'm wondering if the slip-tube that joins the long tube to the water pump became disconnected somewhat or something to that effect. Maybe I'm just being paranoid.
2) My top speed was 30 mph measured using GPS. I was hoping to get it to at least 35.
- The prop has a 15P stamped on the end of string of numbers, so I'm assuming the pitch is 15? It's a 3 blade 14(?)" diameter prop.
- The boat is a 1978 15' Bramco Seaswirl trihull.
- Only my wife and I were in the boat, and I had my tool bag (approx. 30 lbs).
- Lake Washington was real choppy, and boat was hitting the waves pretty hard.
- The boat doesn't have a tach (yeh, I know, I need to get one), so I really don't know what the top end RPM's were. It was up there though.
- The previous owner included a load of ski ropes, so I'm assuming that was his main purpose in using it.
- The boat pulls hard to starboard, so I assume the anode needs adjustment.
Can someone calculate what size prop this engine should have, and can I assume the 15 pitch prop was used to get up to speed, faster, because it was pulling a skier? I'm wondering what size prop I should have that would be a good fit for skiing and top speed. Finally, would a real choppy (big) lake and hitting these waves cause it not to reach the actual top speed?
As always, all input is appreciated.
I finally performed the link/sync on it, today. Amazing how these engines run when the carbs and timing are set just right. It runs great and cranks right up. Actually, it cranks pretty easy for the first start of the day. The hole shot is pretty awesome. It gets right up there. It runs much cooler, too. The pee-hole stream is warm (not scalding, anymore), and you can actually lay hands on the engine without getting burnt. My wife and I had it out on Lake Washington here in Seattle, today, and this is the first time we were able to actually enjoy the boat. I couldn't have gotten this far without input from this forum, and I really do appreciate all the help everyone has given me so far.
Now, here comes the questions:
1) After replacing the impeller, it appeared to have a steady, strong stream during idle. Now, at idle, it appears like a weak drip until I increase the RPM's, and then it comes out in a stream although not like it used to right after replacing the impeller. Is this normal? I can blow back through the pee-hole, and I can hear it gurgling down in the lower unit around the impeller, so I know there aren't any blockages. Additionally, it doesn't run hot. I can put it in gear and turn the prop by hand, and the sound of the new impeller sounds the same now as when it did right after replacement. So, that tells me the impeller is still good and turning, in my opinion. I know one isn't absolutely positive about anything unless it's inspected. I'm wondering if the slip-tube that joins the long tube to the water pump became disconnected somewhat or something to that effect. Maybe I'm just being paranoid.
2) My top speed was 30 mph measured using GPS. I was hoping to get it to at least 35.
- The prop has a 15P stamped on the end of string of numbers, so I'm assuming the pitch is 15? It's a 3 blade 14(?)" diameter prop.
- The boat is a 1978 15' Bramco Seaswirl trihull.
- Only my wife and I were in the boat, and I had my tool bag (approx. 30 lbs).
- Lake Washington was real choppy, and boat was hitting the waves pretty hard.
- The boat doesn't have a tach (yeh, I know, I need to get one), so I really don't know what the top end RPM's were. It was up there though.
- The previous owner included a load of ski ropes, so I'm assuming that was his main purpose in using it.
- The boat pulls hard to starboard, so I assume the anode needs adjustment.
Can someone calculate what size prop this engine should have, and can I assume the 15 pitch prop was used to get up to speed, faster, because it was pulling a skier? I'm wondering what size prop I should have that would be a good fit for skiing and top speed. Finally, would a real choppy (big) lake and hitting these waves cause it not to reach the actual top speed?
As always, all input is appreciated.
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