Return to MarineEngine.com's home page. Home Call MarineEngine.com or send an email message. Contact Info about orders, shipping and returns. Shipping/Returns View your shopping cart. Cart
Need help with your boat parts order? Call 800-209-9624 Monday - Friday 8:30 AM - 5:30 PM EST Order by phone (800) 209-9624
Monday - Friday 8:30 AM - 5:30 PM EST
Free Classifieds Discussion Forum
Topics Topics Edit Profile Profile Help/Instructions Help Member List Register  
Search Last 1|3|7 Days Search Search Tree View Tree View  

PCM start problems

Discussion Forum at MarineEngine.com » Pleasurecraft Marine PCM » PCM start problems « Previous Next »

Author Message
Top of pagePrevious messageNext messageBottom of page Link to this message

Jeremy P.
Posted on Wednesday, July 02, 2003 - 10:14 am:   Edit Post Delete Post View Post/Check IP

Hello, I have a 350 PCM, holley carb..just had it serviced, it was idling rough and stalled when accelerating to plane. Spark plugs replaced, and accelerator pump arm function fixed. Now the damn thing won't start (cold or hot) easily and occasionally backfires while doing so. Other than the starting problem it runs perfectly now. Which confuses me cause if it runs perfect I should have good ignition and gas flow. I've found that if it doesn't start after 5-6 attempts that if I pull the air filter off and hold the choke plate shut it will fire up (hot engine). Got any ideas? Thanks...
Top of pagePrevious messageNext messageBottom of page Link to this message

Daniamarine (Daniamarine)
Posted on Wednesday, July 02, 2003 - 12:12 pm:   Edit Post Delete Post View Post/Check IP

WHEN REBUILT, DID YOU CHANGE THE POWER VALVE?
DID YOU ADJUST YOUR IDLE MIXTURE SCREWS?
DANIA MARINE 1-800-748-7739
THANKS, GABRIEL
Top of pagePrevious messageNext messageBottom of page Link to this message

poker casino473
Visitor
Posted on Monday, March 06, 2006 - 02:34 pm:   Edit Post Delete Post View Post/Check IP

poker casino poker 911
Top of pagePrevious messageNext messageBottom of page Link to this message

dave waller
New member
Username: supra10

Post Number: 1
Registered: 08-2009
Posted on Sunday, August 16, 2009 - 11:19 am:   Edit Post Delete Post View Post/Check IP

Please help!! I have a 92 supra sport with Ford 351. Never had problems starting, the boat was sitting for about 1-month and when I tried to start it again it will not start. It seems like there is an enormous amount of fuel entering the carb. so i had it rebuilt, i am getting spark at the coil and i pulled one of the plugs and i am getting spark there as well , the coil,distrib. cap and rotor are new as well. I removed the fuel line before the mech. fuel pump to see if maybe the carb. was flooding out and ran it dry, a then tried starting fluid to see if it would fire but still nothing Could. Could someone help,summer is almost over.
Top of pagePrevious messageNext messageBottom of page Link to this message

makomark
Senior Member
Username: makomark

Post Number: 1202
Registered: 09-2008
Posted on Sunday, August 16, 2009 - 10:48 pm:   Edit Post Delete Post View Post/Check IP

Dave:

should have started a new thread.

first guess - get your manual out and recheck the firing order - each wire and at both ends. Fords and Chevy's use a different numbering pattern so verify what you did is correct with that manual.

second guess - you mentioned a lot of fuel into the carb and it was rebuilt but not whether the 'flooding' still exists. if so, check the clear tubing at the fuel pump. If its wet, the pump is leaking and needs to be replaced. failure too do this will continue to flood the carb. Also, pull the dipstick and smell the oil. If its smells like gas, change it and the filter, too. Diluted oil will cause bearing failure.
Top of pagePrevious messageNext messageBottom of page Link to this message

dave waller
New member
Username: supra10

Post Number: 2
Registered: 08-2009
Posted on Monday, August 17, 2009 - 08:51 am:   Edit Post Delete Post View Post/Check IP

Yes the flooding still exists with the rebuilt carb. The firing order is correct. But why if I drained the carb. and tried starting fluid would it not fire, if I have spark.
Top of pagePrevious messageNext messageBottom of page Link to this message

makomark
Senior Member
Username: makomark

Post Number: 1203
Registered: 09-2008
Posted on Monday, August 17, 2009 - 01:36 pm:   Edit Post Delete Post View Post/Check IP

Either no compression or spark occurs at the wrong time...sure the distributor went in correctly?
Top of pagePrevious messageNext messageBottom of page Link to this message

dave waller
New member
Username: supra10

Post Number: 3
Registered: 08-2009
Posted on Monday, August 17, 2009 - 01:51 pm:   Edit Post Delete Post View Post/Check IP

did not install new distributor. How could it have no compression when it ran perfect for 2-yrs. Something to do with sitting for a month. Never had a problem with timing and did not adjust or touch distributor.
Top of pagePrevious messageNext messageBottom of page Link to this message

makomark
Senior Member
Username: makomark

Post Number: 1207
Registered: 09-2008
Posted on Monday, August 17, 2009 - 03:14 pm:   Edit Post Delete Post View Post/Check IP

misread - missed the "cap".


It may have compression - that's leaves the fuel and the spark....Have you put a timing light on it to verify the distributor cap and wires function as required?

Checked for fuel in that tube?
Top of pagePrevious messageNext messageBottom of page Link to this message

Robert E. Hunter
Member
Username: shamrock20

Post Number: 80
Registered: 12-2007


Posted on Monday, August 17, 2009 - 03:26 pm:   Edit Post Delete Post View Post/Check IP

I would bet on no spark. A bad wiring harness or a bad ballast resistor could be the problem. A timming light should indicate if there is spark as stated by Makomark.

If you check the distributer besure to use the firing order for a Ford HO engine.
HO is 1-3-7-2-6-5-4-8
Top of pagePrevious messageNext messageBottom of page Link to this message

dave waller
Member
Username: supra10

Post Number: 4
Registered: 08-2009
Posted on Monday, August 17, 2009 - 03:36 pm:   Edit Post Delete Post View Post/Check IP

I pulled two of the plugs and grounded to motor mount and I do have spark, could it be the plugs are fouled and if so would they show a spark?
Top of pagePrevious messageNext messageBottom of page Link to this message

dave waller
Member
Username: supra10

Post Number: 5
Registered: 08-2009
Posted on Monday, August 17, 2009 - 03:38 pm:   Edit Post Delete Post View Post/Check IP

As far as the firing order goes I numbered each plug wire before I removed the old cap and replaced each in same as was when the boat was running fine
Top of pagePrevious messageNext messageBottom of page Link to this message

makomark
Senior Member
Username: makomark

Post Number: 1208
Registered: 09-2008
Posted on Monday, August 17, 2009 - 04:36 pm:   Edit Post Delete Post View Post/Check IP

Usually, a fouled plug won't spark. You can always replace them. On occasion, i've seen plugs show spark when held to the block but misfire in the cylinder.

Robert's observation of the ballast resistor being bad has caused more than one owner to sell his boat.
Top of pagePrevious messageNext messageBottom of page Link to this message

David Kirpich
New member
Username: dkirpich

Post Number: 1
Registered: 09-2009
Posted on Tuesday, September 22, 2009 - 09:13 am:   Edit Post Delete Post View Post/Check IP

I need a wiring Diagram for a PCM Marine Engine 454 long block. 1982 Supra Sport Ski Boat. Any help would be appreciated

Add Your Message Here
Post:
Bold text Italics Underline Create a hyperlink Insert a clipart image

Username: Posting Information:
Only registered users may post messages here. Registration is FREE and easy, click on the REGISTER link at the top of the page. Thanks.
Password:
Options: Automatically activate URLs in message
Action:

Administration Administration Log Out Log Out   Previous Page Previous Page Next Page Next Page

Free Classifieds Discussion Forum
Home | Contact | Shipping/Returns | Cart
Boat Engine Parts Boat Motor Manuals Boat Accessories
About Us | Terms of Use | Privacy Policy MarineEngine.com, 184 Jones Drive, Brandon, VT 05733 USA
© 2009 MarineEngine.com, Inc. All rights reserved. Phone: 802-247-4700 | Fax: 802-301-1034 | eMail: info@marineengine.com