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Steam in tell tale

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Eoinie

New member
Hi
I have a 1984 70 hp Johnson motor. At high revs she planes after a few seconds and when she does she doesn't take in cooling water anymore. I
get steam from the tell tale. When I slow down and she drops down again she starts picking up water again. Any solutions out there?
Thanks
 
Do you have a model # and is the transom 20" high or something else.----New water pump impeller ?----Factory parts or something else?----How did it run for you last season ?----Compression test done ?----Possible blown head gasket ?
 
racerone said:
Do you have a model # and is the transom 20" high or something else.----New water pump impeller ?----Factory parts or something else?----How did it run for you last season ?----Compression test done ?----Possible blown head gasket ?
Click to expand...

Model no. J70TLCRD. I dont know the transom height but the boat is a Shetland Family Four and has the built in transom bay. I do know that the prop sits about 1 or 2 inches above the keel level when trimmed down fully. I checked the impeller when she was out of the water and it looked fine. It also works fine at low and medium revs, and at high revs until she lift out on plane. Compression good across all three cylinders, all three the same. New head gasket fitted.
 
Thanks Racerone
Went to the boat and measured it. 20" from top of transom to keel. 6" from top of transom to water level.
 
Pictures attached. She is a 70HP with a 60HP cover. I never ran her at full speed before now so I'm assuming it is an old issue. Boat not painted recently.
Seems I can only upload one image at a time so 2 to follow.

20220507_111702.jpg
 
Can't upload remaining 2 pics. The one that uploaded was 0.9MB and the other 2 are 1.3 each approx. Is this the issue?
 
For sure, that crud has to be cleaned off. Both motor and boat bottom. If nothing else, it is hurting performance. And water flow across the gearcase sides/water intake/screen.
 
I thought that myself at the start of this thread but I can tell you that all the vents are clear of any blockages. The boat is in freshwater so the soiling is only slime - nothing harder. The tell tale works perfectly well for all the time she is driven to near top speed, but when she rises a little while planing she stops sucking in water.
 
Eoinie said:
I thought that myself at the start of this thread but I can tell you that all the vents are clear of any blockages. The boat is in freshwater so the soiling is only slime - nothing harder. The tell tale works perfectly well for all the time she is driven to near top speed, but when she rises a little while planing she stops sucking in water.
Click to expand...

Ignore what you want.
 
If you are referring to your previous post, I am not ignoring it. I am merely expanding on info I have given. You're being a little over sensitive. Thanks for your contribution.
 
I suspect that the foam may well be an issue. The boat was stored outdoor and uncovered for a few years and the foam was very wet for a while - draining out through the plug holes for ages. It seems drier now though. How would that effect the outboard steaming though?
 
I would say that you have a water restriction somewhere.----Up to you to find it.----All the water will never drain out of the foam.-----It rots the stringers and transom!----This now becomes a safety issue.-----Good luck with it.
 
I have no clue what kind of boat that is. But it sounds to me like you are lifting the water intake above the surface at speed. You can take it from there. I'm too sensitive.
 
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