Volvo 340,loss power on climbs

  • Thread starter Thread starter C.M.F.
  • Start date Start date
C

C.M.F.

It's a Volo 340 with B172 engine (renault engine). Work well, except
ascenting where power almost disappears. Spark plugs are new. Solex Z10
looks without adjustment. I hear soft metalic noise on cylinder head when
high power (perhaps, drive valves, but could be normal). More, par gap/power
gap looks very narow (2800-3300 rpms). Under 2800rpm don't go up at least
overload.

On slopes, with top acelerator pedal, motor firecracker.

Furtermore, user's manual refences a deceleration's mechanism and
tachometer's relay... what is it?, Where is it?

Thanks.
 
C.M.F. said:
It's a Volo 340 with B172 engine (renault engine). Work well, except
ascenting where power almost disappears. Spark plugs are new. Solex Z10
looks without adjustment. I hear soft metalic noise on cylinder head when
high power (perhaps, drive valves, but could be normal). More, par gap/power
gap looks very narow (2800-3300 rpms). Under 2800rpm don't go up at least
overload.

On slopes, with top acelerator pedal, motor firecracker.
Click to expand...

A backfire under full power probably something fairly significant.
Means petrol is being burnt in the manifold or when the exhaust valves are
open.
Possibly - cam belt has slipped.

Or a combination of something affecting the low end (like ignition) and high
end revs (fuel or air problems).
Furtermore, user's manual refences a deceleration's mechanism and
tachometer's relay... what is it?, Where is it?
Click to expand...

I think this is referring to the fuel cut-off under deceleration, but I
wasn't aware 1.7s had this, more common in injections systems. Also UK 340s
didn't have tacho, and on 360s it simply feeds of the coils low voltage
side. Possibly both these things are referring to 1.4 automatics.

Sounds like the Engine is in a bit of a mess, this is the kind of reason I
avoid 1.7s.

Does it tick over ok?
 
Because said:
It's a Volo 340 with B172 engine (renault engine). Work well, except
ascenting where power almost disappears. Spark plugs are new. Solex Z10
looks without adjustment. I hear soft metalic noise on cylinder head when
high power (perhaps, drive valves, but could be normal). More, par gap/power
gap looks very narow (2800-3300 rpms). Under 2800rpm don't go up at least
overload.

On slopes, with top acelerator pedal, motor firecracker.
Click to expand...


I would guess that your ignition timing is out of adjustment.

"Metalic noise on cylinder head when high power" could be detonation
(sometimes called 'pinking', 'pinging', or 'knocking'); "motor
firecracker" is presumably backfiring.

Both of these things can be caused by faulty ignition timing.


--

Stewart Hargrave

I run on beans - laser beans


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Tony Stanley said:
A backfire under full power probably something fairly significant.
Means petrol is being burnt in the manifold or when the exhaust valves are
open.
Possibly - cam belt has slipped.

Or a combination of something affecting the low end (like ignition) and high
end revs (fuel or air problems).


I think this is referring to the fuel cut-off under deceleration, but I
wasn't aware 1.7s had this, more common in injections systems. Also UK 340s
didn't have tacho, and on 360s it simply feeds of the coils low voltage
side. Possibly both these things are referring to 1.4 automatics.
Click to expand...
ok!, but carb have 2 electric dispositives to same electric cable. One for
tick over (electrovalve) and other is in base carb for.......
Sounds like the Engine is in a bit of a mess, this is the kind of reason I
avoid 1.7s.

Does it tick over ok?
Click to expand...
I have this car 3 weeks ago. At first, base carb junction was broken. I
don't know how long was it (previous owner), but mainfold had a crust on all
surface (difficult clean). I clean it and change the junction. And now ticks
over very well. Perhaps exhaust valves don't close due to that crust or
damage by crust. I think doesn't air leakage intake now. Backfire is on
slopes without pedal press.

Can ignition timing adjust in this engine?, if only is that.........

Regards
 
C.M.F. said:
ok!, but carb have 2 electric dispositives to same electric cable. One for
tick over (electrovalve) and other is in base carb for.......

I have this car 3 weeks ago. At first, base carb junction was broken. I
don't know how long was it (previous owner), but mainfold had a crust on all
surface (difficult clean). I clean it and change the junction. And now ticks
over very well. Perhaps exhaust valves don't close due to that crust or
damage by crust. I think doesn't air leakage intake now. Backfire is on
slopes without pedal press.

Can ignition timing adjust in this engine?, if only is that.........
Click to expand...
No, the ignition time is not adjustable directly. But if the timing is out
it is caused by other problems like a slipped timing belt (ie its not on the
right teeth).

I think if the valves didn't close you wouldn't get much compression and it
would be difficult to start.

Exhaust leaks / broken exhausts can cause light back fires on deceleration.
 
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