Ironhead A place to talk about Ironheads.

75 Ironhead Starting Issue

Thread Tools
 
Search this Thread
 
  #21  
Old 12-11-2011, 08:09 AM
IronMick's Avatar
IronMick
IronMick is offline
Stellar HDF Member
Join Date: Jun 2008
Location: London, ON Canada
Posts: 3,177
Received 114 Likes on 94 Posts
Default

Do you know how to check the float level? It must be accurate to within a couple of millemeters.

There should be no fluid [gas, etc] inside the float.

Identify each jet [main, slow, accelerator pump] and the pilot screw area, and ensure that you can blow compressed air or carb cleaner thru each.

Here are some notes for a Keihin butterfly carb. Different carb but much of the process is the same ...

Cleaning a Carb

1. Removing it from the bike should be straight forward. First thing when it is out is to check the pilot screw setting. Turn it all the way in until gently seated counting the number of 1/4 turns; then write this number down; then reset it.

2. I put mine in a vice to remove the screws, and for much of the following work. Wrap in a shop towel; close the vice gently taking extra care with the choke and throttle linkages. The vice is a needed extra pair of hands.

EDIT: A better choice than a plain vice ...


Better one ...



3. You must be very careful handling the float so as to not change the level. You should have the official specs for setting the level as in the FM, and check it, every time you dismantle the carb, as the last thing before putting it back together.

4. The jets are made of brass, a soft metal that is easily damaged. Use an exact correct size screwdriver. I ground a medium flat blade screwdriver down to exact size on my bench grinder to access the slow jet.

5. The general appearance of the inside of the carb is not necessarily a good indication of its condition. It can look spotless and have clogged jets, or look cruddy and have clear jets.

6. Clean each individual part. Do not allow any solvents to contact any rubber parts [tip of needle, o-ring seal for bowl]

7. Make a list of all of the jets and passages for your carb using the carb manual or the FM for the bike. Then ensure that you can blow either compressed air or carb cleaner thru each one.

8. Remove the pilot screw and clean the parts and the passage. The passage contains in this sequence: pilot screw, spring, washer, o-ring. These are very small parts, especially the washer and o-ring. Usually the spring will easily fall out. One time i thought the spring was not in there because it would not fall out; i obtained a new spring and could not get it in! The technique for removing the washer and o-ring is to use a pipe cleaner: stick it in the hole, twist it around, remove it - you should see the washer and o-ring on the end of the pipe cleaner.

EDIT: the washer and o-ring are part of the pilot screw assembly for 1979 on. They are not in the 1978 and earlier Keihin carbs.

Remember that the purpose of the washer is to protect the o-ring from the spring and you will always get them back in in the correct sequence.

9. Dismantle the accelerator pump assembly noting carefully the sequence and orientation of the parts. Clean and inspect the parts. Replace the diaphragm if it is cracked.

10. Check the float level then carefully put it back together. I personally find it very confusing trying to decide which way to bend the tang if it is not correct. If the fuel level is low is the float high or low? Do i need to bend the tang up or down? On the bench the carb is usually upside down, adding to the confusion. Sort all this out before making an adjustment.

Best to replace the original Phillips screws for the bowl with stainless steel socket head screws.
 
  #22  
Old 12-11-2011, 07:10 PM
bmassarani's Avatar
bmassarani
bmassarani is offline
Intermediate
Thread Starter
Join Date: May 2009
Location: Phoenixville, PA
Posts: 46
Likes: 0
Received 0 Likes on 0 Posts
Default

Yeah Mick, you're right - In retrospect I don't know how to adjust the float lever. I sealed it back up and opened the fuel line last night and this morning my drip pan was filled with gasoline.

So I went at it again and removed the reservoir. This time I noticed that the fuel pushrod was misaligned with the idle speed / pump adjustment lever. I've completely removed the carb bowl assembly and I found that the diaphragm for the pump cap assembly was no longer secured.

I've also checked and the main and intermediate jet are clear of any obstructions. But I'm pretty confident that there is no gasoline getting to the engine (along with the float level issue).

I got some SealAll to reattach the diaphragm (is that a good idea?) and now that I've got the carb bowl assembly away from the bike I am going to start testing it more thoroughly.
 
  #23  
Old 12-11-2011, 09:39 PM
IronMick's Avatar
IronMick
IronMick is offline
Stellar HDF Member
Join Date: Jun 2008
Location: London, ON Canada
Posts: 3,177
Received 114 Likes on 94 Posts
Default

I am not familiar with that carb. Is it an S&S? or what? Should be able to find the instruction sheet thru a Google search. Let me know what carb it is if you cannot find the sheet yourself.

I am not familiar with the SealAll product. If it is a silicone type of sealant then you should not use it. Typically a small amount will detach in the float area and get stuck in the inlet or in a jet.

I use Permatex Hylomar to seal the float bowl o-ring in my Keihin butterfly carb. It is sticky and never hardens or breaks off small bits.

http://www.permatex.com/products/aut...ge_Sealant.htm
 
  #24  
Old 12-12-2011, 08:01 PM
bmassarani's Avatar
bmassarani
bmassarani is offline
Intermediate
Thread Starter
Join Date: May 2009
Location: Phoenixville, PA
Posts: 46
Likes: 0
Received 0 Likes on 0 Posts
Default

It's a S&S Super E. I've found this techsheet that I am using:

http://www.sscycle.com/carbquickguide/

http://www.nightrider.com/biketech/d.../super_e_g.pdf
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
lobofang
Shovelhead
11
07-01-2018 09:14 PM
adamk
Sportster Models
17
07-12-2017 06:47 PM
rigger203
Exhaust System Topics
0
07-09-2011 06:45 PM
victoriouz
Exhaust System Topics
16
06-14-2011 04:05 PM
94-Sporty
Exhaust System Topics
3
06-13-2009 03:03 PM



Quick Reply: 75 Ironhead Starting Issue



All times are GMT -5. The time now is 05:48 PM.