Hi all,
I have 1977, 70HP evinrude 2-stroke, 3cyl. (running it on a 15ft fiberglass trihull that weighs maybe 500lbs). I don't know what prop pitch, as the prop is not labled, but appears original.
The motor sat for probably 10+ years unused. I have done a major overhaul on it, and done the following:
Rebuilt carbs (tanked, cleaned, rebuilt with kits)
new spark plugs
New coil packs
Seafoam decarb (yes it was NASTY), but seems clear now.
(ton of stuff to the lower unit but that doesnt apply to my issue).
Compression is:
120 #1 (top)
110 #2 (middle)
125 #3 (bottom)
The problem is this:
When I go to take off the motor goes, bleehhhhh (hard to describe the sound, almsot like a vacuum cleaner sucking really hard), like it's either starved for fuel/air or flooding, then it will either conk out, or slowly start to take off, (RPM's build little by little, till vroom, then it seems fine)...
This is worsened, when say, I am idling down a channel for a while, then go to take off, it can take up to 2 mins before the engine starts to "go". When this is happening, I will get maybe 2k rpm out of it. it will chug along, then suddenly it will take off and be fine again... work great until I let it idle down then problem starts over.
When I don't let it idle down for long, it seems to work just fine, like if I go WOT, down to idle, come off plane, then take off again (fairly quickly), there is no issue, and it runs just fun, takes off just fine... its only after it idles for a bit that it becomes a problem, then wont go.
Motor will always instantly restart afterwards.
When it does get going, and gets up on plane, WOT is 5200rpm (not sure if thats good or bad), with me in it (200lbs more). I dont have a speedo, so don't know how fast I am going.
It also "seems" to be using a lot of gas.. this is the first time I have had it in the water, but test running it around yesterday I went through 8-gallons in about an hour... (running between WOT and idle while trying to figure out this issue).
Any thoughts?
I have 1977, 70HP evinrude 2-stroke, 3cyl. (running it on a 15ft fiberglass trihull that weighs maybe 500lbs). I don't know what prop pitch, as the prop is not labled, but appears original.
The motor sat for probably 10+ years unused. I have done a major overhaul on it, and done the following:
Rebuilt carbs (tanked, cleaned, rebuilt with kits)
new spark plugs
New coil packs
Seafoam decarb (yes it was NASTY), but seems clear now.
(ton of stuff to the lower unit but that doesnt apply to my issue).
Compression is:
120 #1 (top)
110 #2 (middle)
125 #3 (bottom)
The problem is this:
When I go to take off the motor goes, bleehhhhh (hard to describe the sound, almsot like a vacuum cleaner sucking really hard), like it's either starved for fuel/air or flooding, then it will either conk out, or slowly start to take off, (RPM's build little by little, till vroom, then it seems fine)...
This is worsened, when say, I am idling down a channel for a while, then go to take off, it can take up to 2 mins before the engine starts to "go". When this is happening, I will get maybe 2k rpm out of it. it will chug along, then suddenly it will take off and be fine again... work great until I let it idle down then problem starts over.
When I don't let it idle down for long, it seems to work just fine, like if I go WOT, down to idle, come off plane, then take off again (fairly quickly), there is no issue, and it runs just fun, takes off just fine... its only after it idles for a bit that it becomes a problem, then wont go.
Motor will always instantly restart afterwards.
When it does get going, and gets up on plane, WOT is 5200rpm (not sure if thats good or bad), with me in it (200lbs more). I dont have a speedo, so don't know how fast I am going.
It also "seems" to be using a lot of gas.. this is the first time I have had it in the water, but test running it around yesterday I went through 8-gallons in about an hour... (running between WOT and idle while trying to figure out this issue).
Any thoughts?
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