Home 

 Moderated by: Greg Fletcher  
AuthorPost
BrandonDN
Member
 

Joined: 01-31-2021
Location:  
Posts: 10
Status: 
Offline
So my Jensen Healey I just got running and it’s driving now (around the block because of a lack of turn signals and plates for now). But it sounds like it misfires until you push the gas and accelerate a bit. However, if you accelerate too much then it makes a sound like it’s misfiring again. We’re sure that the spark plugs are good and my dad thinks it’s timing, which brings me to the question of what is the correct position for the distributor because we struggled finding the correct answer for the timing. But when you put the choke on a bit, it sounds great other than running a slightly higher RPM than it should (12). Anything will help please and thank you.

discogodfather
Member


Joined: 09-17-2007
Location: San Francisco, California USA
Posts: 221
Status: 
Offline
What carbs do you have and what's the engine like (stock, modified, condition, ignition setup, etc)? How long was it sitting?

BrandonDN
Member
 

Joined: 01-31-2021
Location:  
Posts: 10
Status: 
Offline
It’s a stock four speed. I’m using two stromberg carbs. The engine’s condition is actually pretty good more or less. The distributor is brand new as are the spark plugs.

BrandonDN
Member
 

Joined: 01-31-2021
Location:  
Posts: 10
Status: 
Offline
It’s a stock four speed. I’m using two stromberg carbs. The engine’s condition is actually pretty good more or less. The distributor is brand new as are the spark plugs.

noomg
Member
 

Joined: 08-02-2018
Location: Long Beach, California USA
Posts: 452
Status: 
Offline
Brandon,

First things first, if you don't have a workshop manual, get one, it has the numbers you need. The manual shows 3 to 5 degrees BTDC.

You should certainly check to see your timing is correct, but I suspect that's not where your problem lies. I think the first area I'd look at would be coil, points and condenser.

BrandonDN
Member
 

Joined: 01-31-2021
Location:  
Posts: 10
Status: 
Offline
It’s just difficult to find a manual. Also there aren’t points anymore because it’s an electric distributor and the coil is also brand new. Almost certain I have it wired all correctly too

Dakota123
Member
 

Joined: 03-20-2009
Location: Colorado USA
Posts: 187
Status: 
Offline
Mine acted the same way when one of the carb dampers was hanging up in its bore. Fueling was only more or less correct over a narrow rpm range.

BrandonDN
Member
 

Joined: 01-31-2021
Location:  
Posts: 10
Status: 
Offline
Okay that’s curious. One of the carbs was acting strange. How did you fix that

noomg
Member
 

Joined: 08-02-2018
Location: Long Beach, California USA
Posts: 452
Status: 
Offline
Pull the tops off, clean and lube the pistons, reassemble. It can happen to Zeniths when they've sat for a while.

BrandonDN
Member
 

Joined: 01-31-2021
Location:  
Posts: 10
Status: 
Offline
Sounds like a plan. Thank you all very much for the answers on all my various questions. I’ll post more if it comes up on this issue. Thank you again!

Tom Bradley
Member
 

Joined: 07-15-2013
Location:  
Posts: 203
Status: 
Offline
Idling is where everything tends to be most finicky: timing air-fuel ratio, etc. According to my manual, idle or static timing for Strombergs is 8 deg BTDC. Generally speaking, the more advanced the better as long as you don't get any detonation. 12 BTDC is supposed to be optimum for these engines, but that can depend on what octane gas you can get. Lower octane burns faster so requires less advance.

When you engage the choke you are doing two things: enrichening the air-fuel ratio and increasing the idle speed. Either one could be what is fixing your problem. From what I have read many people find 1200 RPM works best for them. Mine idles more-or-less OK down to 800 RPM but smooths out much better at 1000, so that is where I keep it.

Do you have a manual for the Strombergs? They are available on Amazon. You will need one as well as some special tools such as the one for adjusting the fuel mix.

There is a Facebook Jensen Healy group that has a ton of files of useful information as well as lots more people contributing helpful information. If possible, you should join.



UltraBB 1.172 Copyright © 2007-2011 Data 1 Systems