Inertia starter motor
Discussion
You would not believe the hassle trying to get a starter motor for 1987 X-flow in Belgium. Not much enthusiasm for self builds here. It looks like I will have to get it from the UK. Anyway I just had a chat on the phone from a man at Powerbase Auto Centre in Kent who is going to see if he can get me one or a pre-engaged unit that will fit. Has anyone already been down this road and survived?
Edited by davidball on Saturday 19th July 12:09
Yep. Been there, done that.
You want the good news?
It's an engine-out job, as you have to fit a new ring gear to the flywheel (which in turn means splitting the old ring gear off the flywheel and heating the new one in an oven to expand it before fitting).
The reason the new ring gear is required is that there is a chamfer on the leading edge to aid engagement; inertia starter motors throw the pinion towards the back of the car to engage them (so the chamfer on the ring gear needs to face toward the front) whereas pre-engaged starter motors pull the pinion forwards into engagement (so the chamfer needs to face towards the back).
If you don't change the ring gear when you do the conversion, the ring gear and pinion will chew each other up in no time flat.
My advice is to find a UK supplier for the inertia starter motor; specialist classic Ford breakers should be able to supply them, no problem. Last time I bought one (about a year ago), it cost me about £25, but that was with a serviceable exchange unit to return.
You want the good news?
It's an engine-out job, as you have to fit a new ring gear to the flywheel (which in turn means splitting the old ring gear off the flywheel and heating the new one in an oven to expand it before fitting).
The reason the new ring gear is required is that there is a chamfer on the leading edge to aid engagement; inertia starter motors throw the pinion towards the back of the car to engage them (so the chamfer on the ring gear needs to face toward the front) whereas pre-engaged starter motors pull the pinion forwards into engagement (so the chamfer needs to face towards the back).
If you don't change the ring gear when you do the conversion, the ring gear and pinion will chew each other up in no time flat.
My advice is to find a UK supplier for the inertia starter motor; specialist classic Ford breakers should be able to supply them, no problem. Last time I bought one (about a year ago), it cost me about £25, but that was with a serviceable exchange unit to return.
Edited by Sam_68 on Saturday 19th July 21:25
Call Mick at Redline Components +44 1883 346515. They are the factory authorised outlet for historic Caterham parts, which is now the catergory an Xflow falls into.
Or you can email mick@redlinecomponents.co.uk but beware they are having some ISP issues at the moment. Hopefully fixed by Monday.
Or you can email mick@redlinecomponents.co.uk but beware they are having some ISP issues at the moment. Hopefully fixed by Monday.
Fat Arnie said:
Whats the difference?
Cost.I'm assuming the OP hasn't got a reconditionable exchange unit. A classic Ford specialist will sell you a second hand unit for next to nothing, which you can then use to exchange for a recon unit at any decent motor factors for about £25.
I bought a new electric window motor for my Elan not so long ago;
Lotus Specialist: (much sucking through teeth} 'Can't get hold of 'em, Sir. We happen to have one second hand, but I'm afraid we'll have to charge you £125 for it'
Ford specialist (its a MK1 Escort wiper motor): 'call it a tenner, Gov.'
'Prestige' marque specialists are for people with more money than sense.
No, wait. This is the Caterham forum, isn't it? As you were...
Been there with my old car as well, you can buy a pre-engaged motor from a motor factor and you don't need to take the engine out to change the ring gear. Count how many teeth are on the flywheel, from memory its either ? or 72 (have a K now so long time ago). You can then get a pre-engaged motor with the correct teeth to fit. Give http://www.jameswhiting.com/ a call, he originally gave me the correct motor factor number which provided a Ford starter motor with the correct ring gear for a xflow (pre-engaged)
casbar said:
...you don't need to take the engine out to change the ring gear. Count how many teeth are on the flywheel, from memory its either ? or 72 (have a K now so long time ago). You can then get a pre-engaged motor with the correct teeth to fit.
Casbar,It isn't the number of teeth on the pinion that is the problem; as you say, you can buy different pinions to account for that, if necessary
As I tried to explain above, it's the fact that the pinion is brought into mesh from the opposite side of the flywheel and the ring gear is chamfered on the leading edge, to ease the meshing.
It will work without changing the ring gear, but the ring gear and pinion will chew each other up relatively quickly and Sod's law dictates that you'll be in the South of France without tools when it eventually locks solid in mesh.
Well I ran a pre-engaged motor for some 7 years with no adverse effects. James Whiting had a motor which had the correct pinnion for the ring gear and if all worked really well with no ill effects. Its a while ago now, but I did have to count how many teeth were on the ring gear to make sure the pinnion was correct on the starter motor.
Just did a search on Blatchat, several threads around this, here is the text of the one I started when I fitted my last motor:
Fitted a replacement pre engaged motor this morning, all is well at the moment, but will keep you posted.
def843t,
Try fitting a pre-engaged motor, they produce more starting force with less battery drain. The other problem you may have, is check you have the correct starter motor, as Ford made different motors to suite different flywheels. Some xflows have 110 teeth flywheels and some have seventy something. So if the motor has been replaced a miss match may have occured.
If you have 110 teeth flywheel, and you go pre engaged, you need a 9 tooth ring gear on the motor. Mine according to the box, is from an early Transit.
Fitted a replacement pre engaged motor this morning, all is well at the moment, but will keep you posted.
def843t,
Try fitting a pre-engaged motor, they produce more starting force with less battery drain. The other problem you may have, is check you have the correct starter motor, as Ford made different motors to suite different flywheels. Some xflows have 110 teeth flywheels and some have seventy something. So if the motor has been replaced a miss match may have occured.
If you have 110 teeth flywheel, and you go pre engaged, you need a 9 tooth ring gear on the motor. Mine according to the box, is from an early Transit.
casbar said:
Well I ran a pre-engaged motor for some 7 years with no adverse effects.
...and I fitted one in a Westfield that destroyed itself within about 6 weeks, which is how come I know about the problem in the first place.The pinion teeth issue is another one that some people get away with and some don't - Lotus built a large number of Twin Cam Elans which were fitted with the wrong pinions on the starter motors. Some people went through starter motors on virtually a monthly basis until they realised there was an issue and changed to the correct pinion, some people (particularly in the US, where the majority of the 'wrong' cars seem to have ended up) are still running on the original, incorrect pinion 40 years down the line, with no reported problems.
I guess the question is 'do I feel lucky'?
Ultimately, since the inertia starter motor with the correct number of teeth is still both cheap and readily available, what's the point in spending more money on a pre-engaged starter, just for the privilege of running the risk?
Well, it looks like the switch to a pre-engaged starter is a minefield and I do not want to go down that route until I have exhausted all possibility of getting an inertia replacement. I may have sourced one here in belgium but if not I will check the UK contacts that have been posted. Thanks to all for the help so far.
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