03 Dyna - S&S 98" Build - wont start - help!
Thread Starter
|
Ultimate HDF Member
Joined: Aug 2010
Posts: 5,014
Likes: 739
From: Northern California
03 Dyna - S&S 98" Build - wont start - help!
As the title says I have an 03 Dyna that I replaced the stock 88 cylinders and heads with
She's all back together and although the engine turns over fine by hand/starter, it won't start. After cranking several times there is a backfire. My initial thinking is to go back and readjust the pushrods? I noted that the S&S video on YouTube shows 20 flats while the instructions call for 24 flats?
Also, as there is a vacuum connect for the Harley carb from the fuel valve to the carb. I chose the vacuum port on the super e that is closest to the intake. There is another on the manifold. Any difference between the two? I can smell fuel in the carb but not as strong as I would expect? Also, when I roll the throttle I don't see a spray of gas from the accelerator? The line is a straight shot from the tank valve to the carb. Running between the cylinders as did the stock carb.
I also put the stock Harley ignition /coil back just to eliminate some of the possibilities. Made no difference, still wont start.
Any help appreciated!
- S&S 98" Cylinders
- S&S 79cc heads
- S&S 583 Compression Release cams
- Screamin Eagle Cam Plate/Oil Pump
- S&S Quickee Pushrods
- Dynatec 88 Coil/Ignition Module
- S&S Super e Carb
- Timken Bearing Upgrade
- Harley Tachometer Kit
- Screamin Eagle 2 into 2 exhaust
She's all back together and although the engine turns over fine by hand/starter, it won't start. After cranking several times there is a backfire. My initial thinking is to go back and readjust the pushrods? I noted that the S&S video on YouTube shows 20 flats while the instructions call for 24 flats?
Also, as there is a vacuum connect for the Harley carb from the fuel valve to the carb. I chose the vacuum port on the super e that is closest to the intake. There is another on the manifold. Any difference between the two? I can smell fuel in the carb but not as strong as I would expect? Also, when I roll the throttle I don't see a spray of gas from the accelerator? The line is a straight shot from the tank valve to the carb. Running between the cylinders as did the stock carb.
I also put the stock Harley ignition /coil back just to eliminate some of the possibilities. Made no difference, still wont start.
Any help appreciated!
Last edited by mmesa005; Sep 18, 2016 at 02:02 PM.
Extreme HDF Member
Joined: Aug 2013
Posts: 16,271
Likes: 15,108
From: Somewhere SW
That and the wiring, make sure everything is hooked up properly and you're getting power.
Thread Starter
|
Ultimate HDF Member
Joined: Aug 2010
Posts: 5,014
Likes: 739
From: Northern California
Update
I checked the plugs, wires, coil. I have spark at the plug when cranking the motor. I confirmed I have fuel in the carb and flowing out the accelerator pump when cycling the throttle. I did readjust the pushrods and have the same results, after a couple of seconds of the starter I get a backfire.
I pulled the valve cover boxes and checked for valve opening / closing. Looks good there. I am going to pull the cams and check them next.
In the past when I changed cams/pushrods I was able to move the rear wheel by myself with the bike in 5th gear. After the new cylinders/heads I can move it part way with one hand but need both hands to complete the cycle. I gapped the rings per S&S instructions with the 2nd ring having more gap than the top as per instructions. Top rings are 0.018, 2nd rings .024, oil rings untouched. All spaced per instructions.
As this is a new build is it normal?
I pulled the valve cover boxes and checked for valve opening / closing. Looks good there. I am going to pull the cams and check them next.
In the past when I changed cams/pushrods I was able to move the rear wheel by myself with the bike in 5th gear. After the new cylinders/heads I can move it part way with one hand but need both hands to complete the cycle. I gapped the rings per S&S instructions with the 2nd ring having more gap than the top as per instructions. Top rings are 0.018, 2nd rings .024, oil rings untouched. All spaced per instructions.
As this is a new build is it normal?
Thread Starter
|
Ultimate HDF Member
Joined: Aug 2010
Posts: 5,014
Likes: 739
From: Northern California
Pulled the cams, they look good. Timed correctly, dots on the front line up as did the front chain Cam/Crankshaft sprocket alignment marks.
Not certain where to go next?
Not certain where to go next?
Trending Topics
Outstanding HDF Member
Joined: May 2013
Posts: 3,427
Likes: 164
From: Home
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
10 Things Harley-Davidson Needs to Fix in 2026
Verdad Gallardo
