Go Back   TeamTalk > Maintenance Tips, How-tos and Refurbishing Topics > Engine / Drive Train

Reply
 
Thread Tools Display Modes
  #1  
Old 08-07-2012, 02:43 PM
JaredOSU JaredOSU is offline
TT Regular
 
Join Date: Jun 2012
Boat: Mastercraft Prostar 190 351 Windsor 1:1 Borg Warner
Location: South Central
Posts: 41
Carb Tuning

I have a 1989 Mastercraft Pro190 with a 351 Windsor and 4160 Holley carb. I am trying to tune the carb to where it starts easier when the engine is hot. I have adjusted the metering block air screws to about 1.25 turns as per the manual. Now, sometimes the engine wont start when it is cold (hasn't been running). I have adjusted the electric choke but I may not have it set correctly? Any ideas? Oh, I dont have a vacuum guage either.
Reply With Quote
  #2  
Old 08-07-2012, 03:26 PM
thatsmrmastercraft's Avatar
thatsmrmastercraft thatsmrmastercraft is online now
MC Master Poster
 
Join Date: Sep 2008
Boat: 1977 Stars & Stripes
Location: St. Paul, MN
Posts: 15,164
With the engine cold, pump the throttle once to set the choke. The choke blade should now be almost completely closed. If not, loosen the three screws securing the choke cap and turn the plastic choke cap until the blade just reaches the almost closed point, and tighten the screws. Once started, the choke blade should open fully within a minute or so. If it doesn't open quickly enough, or too quickly, you need to get a new choke cap.
__________________
Peter

SPECIAL PRICE
ST205/75R15 KENDA LOADSTAR ON 15X5 WHITE SPOKE WHEEL, BALANCED & DELIVERED - $125 EACH


Tandem Axle Packages Starting at $569 - 4 Aluminum wheels, 4 ST205/75R14 tires, mount & balance.
Single Axle Package Starting at $319 - 2 Aluminum wheels, 2 ST205/75R14 tires, mount & balance.

CARBURETOR REBUILDING - $125 + PARTS
LED lights, Hubs, Spare Tire Carriers, Chrome & Powder Coated Lug Nuts

PM or email me tiresplease@gmail.com
*** FREE DELIVERY ON ALL ORDERS ***
Reply With Quote
  #3  
Old 08-07-2012, 03:30 PM
JMann's Avatar
JMann JMann is offline
MC Fanatic
 
Join Date: Nov 2008
Boat: 1991 Prostar 190, Indmar 351
Location: West coat, San Francisco bay area
Posts: 671
Send a message via Yahoo to JMann
I set the screws on my metering block to 1 3/4 turns out after a rebuild and it start good warm or cold so I stopped screwing with them. You may need to turn them out a little, try 1.5 turns out and see if it gets better. I think the carb comes factory at 2 turns out and you adjust from there, you may be a little lean.
Reply With Quote
  #4  
Old 08-07-2012, 03:35 PM
thatsmrmastercraft's Avatar
thatsmrmastercraft thatsmrmastercraft is online now
MC Master Poster
 
Join Date: Sep 2008
Boat: 1977 Stars & Stripes
Location: St. Paul, MN
Posts: 15,164
It seems 1.5 turns is about the average.
__________________
Peter

SPECIAL PRICE
ST205/75R15 KENDA LOADSTAR ON 15X5 WHITE SPOKE WHEEL, BALANCED & DELIVERED - $125 EACH


Tandem Axle Packages Starting at $569 - 4 Aluminum wheels, 4 ST205/75R14 tires, mount & balance.
Single Axle Package Starting at $319 - 2 Aluminum wheels, 2 ST205/75R14 tires, mount & balance.

CARBURETOR REBUILDING - $125 + PARTS
LED lights, Hubs, Spare Tire Carriers, Chrome & Powder Coated Lug Nuts

PM or email me tiresplease@gmail.com
*** FREE DELIVERY ON ALL ORDERS ***
Reply With Quote
  #5  
Old 08-07-2012, 03:56 PM
keith3613 keith3613 is offline
TT Regular
 
Join Date: Aug 2004
Posts: 89
I have a 1984 that came from the factory super rich. When I had it overhauled it was discovered that the mixture screws needed to be set 3 and ˝ turns out. The thing runs perfect and starts like it was brand new. Also the nut on the accelerator pump was set so that no slack was present, not like Holley recommends with a feeler gauge. It took me about 2 hours of adjusting to find out all of the “Experts” were wrong about adjusting the mixture screws. I’ll take rich any day over lean and hard starting. Idling rich hurts nothing.
Reply With Quote
  #6  
Old 08-07-2012, 04:03 PM
thatsmrmastercraft's Avatar
thatsmrmastercraft thatsmrmastercraft is online now
MC Master Poster
 
Join Date: Sep 2008
Boat: 1977 Stars & Stripes
Location: St. Paul, MN
Posts: 15,164
Quote:
Originally Posted by keith3613 View Post
I have a 1984 that came from the factory super rich. When I had it overhauled it was discovered that the mixture screws needed to be set 3 and ˝ turns out. The thing runs perfect and starts like it was brand new. Also the nut on the accelerator pump was set so that no slack was present, not like Holley recommends with a feeler gauge. It took me about 2 hours of adjusting to find out all of the “Experts” were wrong about adjusting the mixture screws. I’ll take rich any day over lean and hard starting. Idling rich hurts nothing.
Chances are the idle passages on your carb weren't fully drilled from new. I have seen this on two automotive OE carbs from mustangs back in the late 80's. That might explain why you need the increased and immediate accelerator pump stroke. Most importantly, your boat is running properly.
__________________
Peter

SPECIAL PRICE
ST205/75R15 KENDA LOADSTAR ON 15X5 WHITE SPOKE WHEEL, BALANCED & DELIVERED - $125 EACH


Tandem Axle Packages Starting at $569 - 4 Aluminum wheels, 4 ST205/75R14 tires, mount & balance.
Single Axle Package Starting at $319 - 2 Aluminum wheels, 2 ST205/75R14 tires, mount & balance.

CARBURETOR REBUILDING - $125 + PARTS
LED lights, Hubs, Spare Tire Carriers, Chrome & Powder Coated Lug Nuts

PM or email me tiresplease@gmail.com
*** FREE DELIVERY ON ALL ORDERS ***
Reply With Quote
  #7  
Old 08-08-2012, 12:06 AM
j.mccreight@hotmail.com's Avatar
j.mccreight@hotmail.com j.mccreight@hotmail.com is online now
MC Maniac
 
Join Date: May 2010
Boat: 1989 MasterCraft TriStar 190 SE
Location: Houston, TX
Posts: 3,334
Quote:
Originally Posted by JaredOSU View Post
I have a 1989 Mastercraft Pro190 with a 351 Windsor and 4160 Holley carb. I am trying to tune the carb to where it starts easier when the engine is hot. I have adjusted the metering block air screws to about 1.25 turns as per the manual. Now, sometimes the engine wont start when it is cold (hasn't been running). I have adjusted the electric choke but I may not have it set correctly? Any ideas? Oh, I dont have a vacuum guage either.
Only proper way to tune or adjust the carburetor is with a vacuum gauge, too many other variables in play, there are some great tuning tips from holley on youtube...
__________________
James

1989 MasterCraft TriStar 190 SE
Reply With Quote
  #8  
Old 08-08-2012, 01:37 AM
thatsmrmastercraft's Avatar
thatsmrmastercraft thatsmrmastercraft is online now
MC Master Poster
 
Join Date: Sep 2008
Boat: 1977 Stars & Stripes
Location: St. Paul, MN
Posts: 15,164
Vacuum gauges are cheap and there is no reason not to use one if you are serious about tuning your carb. With that said, I have tuned plenty of carbs by rpm only and while it takes a little more patience, a person can do a fine job. Same thing with timing. A timing light makes it a simple job, but an engine can be timed by ear and cautious runs while getting to the sweet spot.
__________________
Peter

SPECIAL PRICE
ST205/75R15 KENDA LOADSTAR ON 15X5 WHITE SPOKE WHEEL, BALANCED & DELIVERED - $125 EACH


Tandem Axle Packages Starting at $569 - 4 Aluminum wheels, 4 ST205/75R14 tires, mount & balance.
Single Axle Package Starting at $319 - 2 Aluminum wheels, 2 ST205/75R14 tires, mount & balance.

CARBURETOR REBUILDING - $125 + PARTS
LED lights, Hubs, Spare Tire Carriers, Chrome & Powder Coated Lug Nuts

PM or email me tiresplease@gmail.com
*** FREE DELIVERY ON ALL ORDERS ***
Reply With Quote
Reply

Thread Tools
Display Modes

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


All times are GMT -4. The time now is 05:29 PM.