Reply
 
Thread Tools Search this Thread
 
Old 23 October 2008, 18:47   #11
Member
 
Country: UK - England
Town: cornwall
Boat name: nothing
Make: rib eye 430
Length: 4m +
Engine: tatsu 50
MMSI: 666
Join Date: Mar 2006
Posts: 1,916
Thats good Easyrider I have been promised a PDF manual from Extreme Marine but still waiting

and for sure the stealer didn't check that when he did the "first service" read tinker about and rev up a few times

Is there also a description of the carb linkage setting / balance

Iam used to timing lights and vacuum guages , this reminds me of an old fergie tractor i used to work on
__________________

__________________
ian parkes is offline   Reply With Quote
Old 24 October 2008, 14:41   #12
Member
 
Country: UK - England
Town: Sussex
Make: Ceasar Surfcat
Length: 4m +
Engine: Tohatsu 50hp
Join Date: May 2006
Posts: 105
Quote:
Originally Posted by ian parkes View Post
Thats good Easyrider I have been promised a PDF manual from Extreme Marine but still waiting

and for sure the stealer didn't check that when he did the "first service" read tinker about and rev up a few times

Is there also a description of the carb linkage setting / balance

Iam used to timing lights and vacuum guages , this reminds me of an old fergie tractor i used to work on
I havnt found anything for the carb balancing yet-i asked the tech guy at tohatsu uk about a service manual a few weeks ago-he said they were waiting for some to come in, but you can only get them through dealers though.
I forgot to answer a quesion you asked on your other thread about mixture settings- i'll go and find the thread and tell you my latest findings
__________________

__________________
Easyrider is offline   Reply With Quote
Old 24 October 2008, 17:10   #13
Member
 
Country: UK - England
Town: cornwall
Boat name: nothing
Make: rib eye 430
Length: 4m +
Engine: tatsu 50
MMSI: 666
Join Date: Mar 2006
Posts: 1,916
I expect the manual will just give set up measurements for the linkage rods just like it does for the timing .
It seems to me what happens is that the tickover screw gets turned up to compensate for a badly set motor .
__________________
ian parkes is offline   Reply With Quote
Old 26 October 2008, 11:00   #14
Member
 
Country: UK - England
Town: Newquay
Boat name: B-Pacific
Make: Halmatic
Length: 6m +
Engine: Inboard diesel
Join Date: Sep 2008
Posts: 8
Slow zapcat

I found with mine that the trim seriously affects the performance, to the point of having to be virtually milimetre perfect. Does it have a prop guard? Taking this off will increase speed noticeably. Sounds like running on two cylinders though. Check the bottom plug which gets wet quite easily.
__________________
davepetts is offline   Reply With Quote
Old 26 October 2008, 14:47   #15
Member
 
Country: UK - England
Town: cornwall
Boat name: nothing
Make: rib eye 430
Length: 4m +
Engine: tatsu 50
MMSI: 666
Join Date: Mar 2006
Posts: 1,916
Quote:
Originally Posted by davepetts View Post
I found with mine that the trim seriously affects the performance, to the point of having to be virtually milimetre perfect. Does it have a prop guard? Taking this off will increase speed noticeably. Sounds like running on two cylinders though. Check the bottom plug which gets wet quite easily.

Glad its not just me . I have a theory that the motor doesn't like being fully tilted for any length of time , which I have to do when trailering . I only seem to oil a plug just after launching now as I don't tilt the motor up fully if iam stopped at the beach . The choke working on the lower 2 carbs only is also a cause i think .

Would also be nice if someone made some sort of fine screw adjuster for the trim
__________________
ian parkes is offline   Reply With Quote
Old 11 December 2008, 01:15   #16
Member
 
Country: Ireland
Town: Ardmore
Boat name: Wavehopper
Make: Cobra 6.65 HD
Length: 6m +
Engine: Yam 150 hpdi
Join Date: Dec 2006
Posts: 136
Probably stating the bleedin' obvious, but are you running all tubes at correct pressures (especially hijackers)? This can have a huge affect on speed
__________________
blimp is offline   Reply With Quote
Old 11 December 2008, 18:47   #17
Member
 
Country: Canada
Town: Rigaud, Que.
Boat name: Rigaud Explorer
Make: 6m Bombard
Length: 6m +
Engine: Yam115
Join Date: Aug 2008
Posts: 90
Everyone always tend to think theirs something wrong with the motor and maybe so. First off does it sound like it's not firing properly? What are your rev's @ WOT? What height is your motor mounted at (prop shaft centerline where is it in refference to the bottom of the boat)? What prop exactly are you running because different type with different performance depending on what you want and your set up. Are the tubes properly inflated?

Need more info to get the CAT guy's to help but usually the wrong prop and engine height are your worst enemy.
__________________
Rigaud is offline   Reply With Quote
Old 18 December 2008, 16:26   #18
Member
 
Locozodiac's Avatar
 
Country: Other
Town: Lima-Peru
Boat name: Nautile
Make: Sea Rider Boats
Length: 4m +
Engine: Tohatsu 18 /30 HP
Join Date: Sep 2007
Posts: 1,706
Quote:
Originally Posted by Rigaud View Post
Need more info to get the CAT guy's to help but usually the wrong prop and engine height are your worst enemy.
I will agree with that comment. Tohatsu engines are very prone to give you wot performance problems if engine is not adjusted/working on recommended factory height specs. Is your cat/engine combo splashing too much water on transom area ? If so, you are loosing top rpm and final speed because of water drag against tail. Your engine, anticav plate/water level should be between 10 to 30 mm according to service manual.

Correct/adjust engine height if necessary, then proceed to put a taco and test engine max revs available at wot, with current pitch size check if under or over reving untill correct max revs are obtained, repitch if needed.

Happy Boating
__________________
Locozodiac is offline   Reply With Quote
Old 19 December 2008, 06:26   #19
Member
 
Country: UK - Scotland
Boat name: Wildheart
Make: Humber/Delta Seasafe
Length: 5m +
Engine: Merc 60 Clamshell
MMSI: 235068449
Join Date: Apr 2007
Posts: 4,610
Stepping back slightly form the problem it sounds like it;s not making max available RPM - Zapcats were designed to runs with Tohatsu 50's? I would imagine even if you messed up the trim spectacularly, it should make a reasonable effort to ge to max RPM. As someone said earlier - a 3- cyl 2 -stroke will not sound spectacualrly rough with only 2 cyls firing, but due to the two remaining cyls having to compress the air, only to get nothing back out in the form of a "bang", it feels more like half than 2/3 throttle.

As an example when i got the Merc it ran Ok at idle, but when I first opened the throttle it did a half hearted impression of a 25. Took the plugs out, bottom one was literally dripping with oil, middle was not so bad but still manky. Changed them, puttered out the marina (even sounded better at tickover) pushed the lever forward & was nearly thrown off the back of the seat!

Moral of the story: Spark plugs are cheap, and don't like being drenched in oil! I'd buy a new set of plugs. What's the worst that can happen? - you end up with a spare set for the next service.


If you are towing, a good idea is to pull the fuel connector before you come ashore or when you are flushing & let the engine drink the contents of the carb bowls. It's not a problem with auto mixers, but also saves oil build up as the fuel evaporates if running premix.
__________________
9D280 is offline   Reply With Quote
Old 19 April 2009, 08:10   #20
Member
 
Country: Netherlands
Town: Kats
Boat name: Kikkie 2
Make: ZapCat
Length: 4m +
Engine: Yamaha 55 !
Join Date: Oct 2008
Posts: 6
Just a question

Hi Guys,

I'm getting into the ZapCat's as well and I have a question :

Does somebody know the exact height of the cav-plate ? To what part of the boat can I relate it to set the correct height ? I was told to go a couple of centimeters above the center line of the high-jackers, is that correct ?

Thanks guys,
Martin
__________________

__________________
Martin Kik is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 10:34.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.