tune up and dizzy springs
Printed From: CorrectCraftFan.com
Category: Repairs and Maintenance
Forum Name: Engine Repair
Forum Discription: Engine problems and solutions
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=3517
Printed Date: November-23-2024 at 10:22am
Topic: tune up and dizzy springs
Posted By: jimbo
Subject: tune up and dizzy springs
Date Posted: May-05-2006 at 10:13pm
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How often do y'all do a tune up? Plugs, cap, rotor, PCV? It's been 1-1/2 years for me but I think it's still too soon. What do y'all think?
I'm noticing an unburned fuel smell in the exhaust at idle and wondering where to start. It's also kinda hard to start. It starts then dies unless I keep it at about 2-3K rpms till it warms up. If it dies, I have to crank it several times to get it going again. I'm thinking the carb may need adjusting (which I know nothing about)since I've replaced the fuel pump and unclogged the dip tube. Or I need new springs in the distributor. They seem kinda week. The timing advances like it should but it doesn't come back to idle easily. I have an 84 SN with 351W with the Presolite Dizzy that I converted to EI some time ago. I looked on Summit Racing and I saw some springs but I wasn't sure which ones to get. They have cam/spring kits for not much more and that's the way I was thinking of going. Any thoughts? To some up the rambling: 1. How often is a tune up good for? 2. Does my problem sound likly to be carb or distributor springs? 3. What springs or what spring/cam kit should I get? Or just go to a shop? Thanks James |
Replies:
Posted By: nuttyskier2002
Date Posted: May-05-2006 at 11:09pm
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How are you checking your timing advance? Are you using a timing light? When you say "it doesn't come back to idle easily" are you refering to the timing advance or the engine speed? To check your distributor for advancing and retarding of the timing you need to use a timing light. The ones with the varible strobe delay (knob on the back) are best to use for this. If your carb doesn't return to idle easily you might need a new accelerator return spring. Are the springs you are looking at with Summit for a prestolite distributor? If not, don't waist your money, they won't be right. Marine distributors use heavier weights and springs than their automotive counterparts. How do your plugs look? If your don't know what they should look like get help here. If they are tan to light brown in color (the electrodes) and gap is good (.035") they are okay. If your engine isn't running good (poor performance, bad gas mileage,....) ignition is allways where to start. If you've tuned it all up and things still aren't right,..move on to the carb. The PCV valve dosen't need to be changed very often. If you shake it and it rattles, it's okay. Hope this helps! Write back if you have specific questions. I'll try to help. ------------- 95 Malibu Echelon w/Mercruiser 350 Magnum Skier Former boats: 88 Ski Centurion Tru Trac II 59 Chris Craft Capri (woody) |
Posted By: jimbo
Date Posted: May-06-2006 at 12:14am
Yes, but not a varible strobe light. When I back off the gas, it still idles around 1200 rpms and around 18-20 BTDC. I have to gun it a couple of time to get it to come back.
Both
No, I didn't see one specfically for Prestolite. Is there a better source?
I haven't pulled the plugs yet. Maybe Sunday. |
nuttyskier2002 wrote:Posted By: nuttyskier2002
Date Posted: May-06-2006 at 7:55am
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If the butterfly valve on the carb doesn't come all the way back to the idle position when you throttle back completely on the lever then you need to fix this first before you can expect your timing to return to it's base at idle. You might need a stronger return spring to pull back the throttle on the carb or your cable may need to be adjusted if it's not binding. So let's fix this first and I'll bet your timing issue will be fixed too. If not, we'll continue from there.
Any springs you buy from Summit are not going to be a direct replacement and you are going to spend lots of time trying to get your timing curve right if you go that route. Right now I don't know of a source to tell you to try for the springs. I bought a shaft for my distributor about 2 years ago and it came with springs and weights. So I have an extra set. ------------- 95 Malibu Echelon w/Mercruiser 350 Magnum Skier Former boats: 88 Ski Centurion Tru Trac II 59 Chris Craft Capri (woody) |
Posted By: jimbo
Date Posted: May-07-2006 at 11:34pm
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I pulled a couple of plugs and they looked fine. Then I pulled one that had the outside porcelain cracked on it. I don't know if I cracked it when I pulled it or it was like that before. Anyway, I ended up changing all the plugs.
I adjusted the electric choke and that tighened the butterfly valve response. It also Idles lower and starts easier. I don't know if it's working properly now but I'm going to start a new thread for help on it. I'm holding off the distributor springs for now. |