Twin H4s & other starting issues.

[hanlminiman]

Thank you Guy and Mark for your observations.
Must admit I am beginning to think the flywheel is the source of the problem as there was evidence of metal filings on the cover and the bendix teeth looked chipped but no more than spare motors I have.
Hey ho. The joys of Mini ownership.
Cliff

[mk1]

The most common issues in this area are that Pre-engaged & inertia components have been mixed up. Starter & flywheel need to be of a common type.

[hanlminiman]

It should be a 421 (107teeth). We'll see soon? The bendix is 9 tooth.

[mk1]

Hope you manage to get sorted very soon.

[Polarsilver]

Had starter spinning & not engaging issues it would throw out rather then spin the motor over .. checked & counted up the ring gear teeth yes they were correct .. Then changed /tried another two 9 teeth Starter Motors .. even tried a new MS Starter Motor & still troublesome .. last thing was take out starter motor & with a thin Flat File with fine teeth .. take off the Burr that had built up on the starter ring gear teeth & this seems to have improved things when Bendix fires in.

[hanlminiman]

That's interesting Polarsilver. 2 of my 9 tooth starter motors look like they have the burr you mention. Worth a try, I'll have a go.
Thanks.
Mark, could you rename this thread Twin H4s & starting issues please. Thanks

[hanlminiman]

Just realised that I haven't updated this thread for some time.
Ring gear separated from flywheel! (not naming supplier !) New MED flywheel (107) and Hi Torque starter motor (9) fitted. Then it started and it ran well but still need to work out starting procedure and adjust choke control. Much happier now. Hope to be back on the road again soon.
Thank you everyone for you comments and advice.
Cliff

[Herbert]

I had exactly the same problems last week with my H4's. I changed everything. It turned out to be fuel. I took the lids off the carbs, and it was water! I drained all the fuel and chucked it down a drain. Put I 5 liters of e5 and it started on the button.

[AndyPen]

I had exactly the same problems last week with my H4's. I changed everything. It turned out to be fuel. I took the lids off the carbs, and it was water! I drained all the fuel and chucked it down a drain. Put I 5 liters of e5 and it started on the button.

Be careful with that water, I had the same before I used additives or removed the ethanol... it is nasty stuff I'm told, and a great weedkiller!

[hanlminiman]

Hello all
I'm a very happy bunny today as it started almost on the key this afternoon.
After trolling YouTube videos for a few weeks I thought I'd go back to basics and adopt a gently/gently approach.
One carb was definitely "iffy" so I thought I would strip it down. Basically, float in chamber in errant carb was upside down, float fork was not "perfect." Fuel drained, fuel filter cleaned and new fuel added.
Yay - it starts from cold.
Thanks for all your advice.
Might take it out for a run locally tomorrow and take photos.
Cliff
ps did take a video of it running today and it sounded sweet but I must get the carbs set up properly. Southam here I come.

[rolesyboy]

I mentioned this earlier in the thread as I experienced similar issues with a shuttle that was jamming in the brass ferrule. When you say the float chamber was 'upside down' that's quite an achievement though? Do you mean the shuttle was upside down? Interested to hear a bit more detail.

[hanlminiman]

Sorry, should have read float in chamber.
If you look at WZX 1303 image on the Burlen website the brass float has 2 parts with the upper section welded to lower part.

[AndyPen]

Years ago I had one of those brass floats go slightly porous and it partially filled with petrol. I imagine the leak was on the seam. Took me ages to spot that and no doubt E 5 fuels won’t help!

[Catmint]

had this one go last year, seam was the strongest bit !

[mk1]

Great news!
Well done Cliff.

[JeremyD]

The problem I have found with starting with H4s is the choke. The initial pull lifts the two levers which turns the cam to increase idle. That does not assist starting. Starting requires the mixture to be richend and that requires the jets to be pulled down away from needles. That’s the next move on the choke which is very difficult. The answer is to unscrew the cam screw then adjust the choke cable so that the levers have already started to to turn the cam. Adjust it so that the can only has a 1/4 turn before jets are pulled down. You would have to remove the dash pots to see this. You will also need to readjust the screw on the cam.

[hanlminiman]

Jeremy. Thank you for your advice. My solution has been to ignore the choke cable system and start the engine from inside the engine bay using the button solenoid. Works very well and last week and I had no trouble restarting the engine after a couple of hours at a show, in fact 1st turn of the ignition switch.

[AndyPen]

Jeremy. Thank you for your advice. My solution has been to ignore the choke cable system and start the engine from inside the engine bay using the button solenoid. Works very well and last week and I had no trouble restarting the engine after a couple of hours at a show, in fact 1st turn of the ignition switch.

I have an old tent peg remover tool for that. The size and rigidity of the metal plus the shape of the handle seem made for it. Cheap as chips too

https://www.ebay.co.uk/itm/293134936177 ... kKEALw_wcB

[970s]

Having learned the H4 starting problem, I would like to share a little of my experience, we live in the tropic climate in Hong Kong, a proper tuned SU setup does not required choke at all while start up engine, only in the cooler Winter morning will need more cranking to start the motor, I choose the same setup as Mark, i.e. to connect only one carb to the choked cable and no fast idle cam is used in the set up, it just enrich the mixture a little, which is sufficient and require less maintenance in daily street running.


AL

[mk1]

As I have said MANY times before, there are 2 really easy solutions to the heavy pull issue, either fit a larger choke cable knob, that's easier to pull, or my preferred method which is to connect the cable to one carb only. It is easy to pull & works a treat.