View unanswered posts | View active topics It is currently March 29th, 2024, 8:40 am



Reply to topic  [ 28 posts ]  Go to page Previous  1, 2, 3  Next
 Backfire 
Author Message
Firing on two.

Joined: February 17th, 2009, 8:43 pm
Posts: 567
Location: NOrWAY
Post Re: Backfire
Roger V wrote:
Is the choke pull off diaphragm perforated?


Hm.... That's the only thing on the two carbs I haven't checked. They are working though, so it cant be a big holes in them. If any.

Spark plugs haven't been checked, but are due for a replacement. They will be replaced when I do the manifold gaskets, re-torquing heads and adjust valves. Hopefully I'll manage to save the exhaust studs. I have not had the manifold off, on this engine before. (Second one in the car)

Today I cleaned and checked carb 1, the one I took off the other day. It was clean (on the inside) after many years of service in the car. Proper fuel filter is a good thing. The float hight was waaay to high, 12mm.
I adjusted it to 15, a little higher than the 18mm specs, after an advice from Ken I found online.
Other than that I didnt find any problems with it. I decided to put it back on to see what happened. The lean running at light to mid open throttle, which appeared with carb 2, disappeared. Carb 2 had the float high set to 18mm. Can that be the reason for the lean running? The car is now back to how it was, EXCEPT, the hard starting is still gone with carb 1. It starts so easy now, so the hard starting was down to the air leak at the base of the carb.
So, at least one problem is solved :)

The flat spot at mid throttle is still there though. And I suppose, the backfires. I dont know yet, as I must use the car a bit for it to happen. Will be driving 500km the next two days so I'l find out soon enough.

If there really IS an airleak in one or both of the intake manifold gaskets, it will explain both the backfires and the flat spot I guess. To be continued....

_________________
Vennlig hilsen, Eirik
Image
Five 2CV's, DS 21 ieh Pallas -70, DS 23 h Pallas -75, CX 25 GTi automatic -89, XM 2,0i -90
And a Heinemann Z412 -80


July 15th, 2020, 9:14 pm
Profile
Firing on two.

Joined: February 17th, 2009, 8:43 pm
Posts: 567
Location: NOrWAY
Post Re: Backfire
If I never get rid of that backfire, I have found a way to live with it :lol: :P

Image

The spring is not as compressed as it looks, it's about 4 mm movement. Hopefully it's enough to save the airfilter from breaking up more than it has.

_________________
Vennlig hilsen, Eirik
Image
Five 2CV's, DS 21 ieh Pallas -70, DS 23 h Pallas -75, CX 25 GTi automatic -89, XM 2,0i -90
And a Heinemann Z412 -80


July 15th, 2020, 9:27 pm
Profile
Firing on two.

Joined: February 17th, 2009, 8:43 pm
Posts: 567
Location: NOrWAY
Post Re: Backfire
Quick, silly cuestion: Are these intake or exhaust gaskets? I believed them to be intake, but not so sure anymore? Liquid gasket on the intake gaskets, yes or no?

Image

_________________
Vennlig hilsen, Eirik
Image
Five 2CV's, DS 21 ieh Pallas -70, DS 23 h Pallas -75, CX 25 GTi automatic -89, XM 2,0i -90
And a Heinemann Z412 -80


July 15th, 2020, 9:33 pm
Profile
Firing on two.
User avatar

Joined: March 21st, 2013, 12:04 am
Posts: 1577
Location: Exeter, Devon
Post Re: Backfire
viewtopic.php?f=5&t=6044&hilit=float+height&start=150

Thats the measurement with the carb gasket on.
I get confused with this. Which is the weaker mix, 12mm, or 18mm?

They suggest gaskets should be dry, but I smear them with sealant. Dont forget to clean up the exhaust flanges, or it will end in swearing. If your worried about the exhaust studs! I cut the nuts off with a very sharp cold chisel. :)

_________________
If you can't fix it with a hammer, it's probably electrical (or, an electric fuel pump!) ....


July 15th, 2020, 9:51 pm
Profile
Firing on two.

Joined: February 17th, 2009, 8:43 pm
Posts: 567
Location: NOrWAY
Post Re: Backfire
Measure with the gasket, yes. 12mm means the fuel goes higher in the bowl, so I guess 18 is leaner than 12.

I'm not gonna dick around, I'll be cutting the nuts off.
Not even gonna try loosening them first. I have new ones, in shiny copper.
Was thinking using a dremel, then a chisel. If they break, I'll probably get the rest out with my welder. But Not sure I have new studs. It'll be easier not snapping them off.

_________________
Vennlig hilsen, Eirik
Image
Five 2CV's, DS 21 ieh Pallas -70, DS 23 h Pallas -75, CX 25 GTi automatic -89, XM 2,0i -90
And a Heinemann Z412 -80


July 15th, 2020, 10:38 pm
Profile
Firing on two.
User avatar

Joined: October 22nd, 2014, 10:59 pm
Posts: 1994
Location: South-Limburg
Post Re: Backfire
What type of ignition do you have?


July 15th, 2020, 11:48 pm
Profile
Firing on two.

Joined: February 17th, 2009, 8:43 pm
Posts: 567
Location: NOrWAY
Post Re: Backfire
DG Nition. Good stuff.

_________________
Vennlig hilsen, Eirik
Image
Five 2CV's, DS 21 ieh Pallas -70, DS 23 h Pallas -75, CX 25 GTi automatic -89, XM 2,0i -90
And a Heinemann Z412 -80


July 16th, 2020, 2:27 pm
Profile
Firing on two.
User avatar

Joined: October 22nd, 2014, 10:59 pm
Posts: 1994
Location: South-Limburg
Post Re: Backfire
Is it still fixed well to the cam? No play?


July 16th, 2020, 5:37 pm
Profile
Firing on two.
User avatar

Joined: March 21st, 2013, 12:04 am
Posts: 1577
Location: Exeter, Devon
Post Re: Backfire
So! Sorted yet? :)

_________________
If you can't fix it with a hammer, it's probably electrical (or, an electric fuel pump!) ....


July 22nd, 2020, 8:35 pm
Profile
Firing on two.

Joined: February 17th, 2009, 8:43 pm
Posts: 567
Location: NOrWAY
Post Re: Backfire
No..... Two, one on each head off course, are not re-usable. F me. This job went exactly as I feared. So, it's in parts now, with a good engine, left useless. I tried hammering, heating and welding. They dont move. I dont know what to do. I went in and had a few beers. Wondering if life will be better without cars. I know these Islands where there are no cars at all..... A tropical one would be my choice. All I needed would be flip flops and a bicycle.

_________________
Vennlig hilsen, Eirik
Image
Five 2CV's, DS 21 ieh Pallas -70, DS 23 h Pallas -75, CX 25 GTi automatic -89, XM 2,0i -90
And a Heinemann Z412 -80


July 22nd, 2020, 9:34 pm
Profile
Display posts from previous:  Sort by  
Reply to topic   [ 28 posts ]  Go to page Previous  1, 2, 3  Next

Who is online

Users browsing this forum: No registered users and 97 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group.
Designed by STSoftware for PTF.