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starter motors
brynhamlet - 28/3/08 at 10:38 AM

Before you all ask it's tuned 1600cc Ford OHV

The problem is when the starter motor (inertia type) is in the engine it's stalling. The motor has been reliable up to now with no problems, so I know its the correct one. When the motor is out of the engine it spins freely if connected to the battery with jump leads. The earth on the car goes from the battery to the chassis and then using a seperate cable to the engine. I'm thinking the earth might be failing under load and am thinking of putting an earth straight to one of the bolts on the staarter motor

Any thoughts

Paul TigerB6 - 28/3/08 at 10:43 AM

Sounds like you are on the right track with an earthing issue. I have put two seperate earthing straps from the engine to the chassis and then a single one from there to the battery but ideally would have like to run one direct from the engine to the battery.

Take it you have given all earthing points a good clean??

Mr Whippy - 28/3/08 at 10:45 AM

is the cable getting hot? sure sign that it needs replaced. Try cranking it over for about 10 seconds and then put you hand on all the connections, chassis ones especially, it will be very warm where it needs cleened.

snapper - 28/3/08 at 10:47 AM

I have an earth from battery to chassis close to starter motor from there another to starter motor to bell housing bolt, then another cable from the starter motor bolt to the engine to bellhousing bolt.
I have also put the earth strap from the gearbox central mounting bolt to the chassis.

britishtrident - 28/3/08 at 11:04 AM

Simple the ignition has too much static advance.

02GF74 - 28/3/08 at 11:18 AM

quote:
Originally posted by britishtrident
Simple the ignition has too much static advance.


then remove inition leads, if starter continues to run, ^^^ that is the cause.

check all connections, earth and poistive cable to soleniod and battery. could be somehting insdie the motor such as brushes or commutator (ooh, look at you with those long technical words!!)

brynhamlet - 28/3/08 at 12:05 PM

Only started thinking about it this morning so haven't tried to sort the earth out.
But it sounds like from the kind advice I am probably right, either that or the starter motor which came out of the original 1979 car might need new brushes or maybe just chucking away.

Oh and for britishtrident the advance is spot on. The engine runs perfectly, when I get started!!!

UncleFista - 28/3/08 at 01:15 PM

quote:
Originally posted by brynhamlet
Oh and for britishtrident the advance is spot on. The engine runs perfectly, when I get started!!!


My crossflow ran great once it'd started too, but it was a bitch to turn. Once we switched to megajolt I retarded the ignition under 500rpm, helped starting no end.

britishtrident - 28/3/08 at 01:21 PM

quote:
Originally posted by brynhamlet
Only started thinking about it this morning so haven't tried to sort the earth out.
But it sounds like from the kind advice I am probably right, either that or the starter motor which came out of the original 1979 car might need new brushes or maybe just chucking away.

Oh and for britishtrident the advance is spot on. The engine runs perfectly, when I get started!!!


I think you completely misunderstand understand what I am saying the problem is STATIC advance. This is an old problem that has been encountered time and time again on modded engines.

This is a very common problem on Ford Kent, It is caused by the distributer having an insufficient number of degrees of centrafugal advance. If you have a side entry Lucas distributer to accomodate Webers it is most likely a Lotus Twin cam distributer -- these have only 10 distributer degrees of centrafugal advance.

As a result on a tuned engine if the distributer is set to give best running/power output the static advance will be too great and at starter cranking speed the engine will try to start backwards against the starter motor, ie stalling the starter.

One way round it is to dismantle the distributor, remove the shaft and file (ie Dremmel) away some material from the "beak" of advance stop to give between 2 and 4 degrees more distributor advance.

When reassembled the static iginition timming can be retarded by between 4 & 8 crankshaft degrees without reducing the advance & power output in the working power band of the engine.

In addition pinking on unleaded fuel will be less likely because in the speed band where pinking occurs 1200 to 2000 rpm the engine will have less advance.

However a better solution is either a properly customised distributer (aldon) or a mapped ignition system (Megajolt).

http://www.teglerizer.com/mgstuff/lucastuning.pdf

http://www.aldonauto.co.uk/aprods.htm



[Edited on 28/3/08 by britishtrident]

[Edited on 28/3/08 by britishtrident] Rescued attachment tech0015f.jpg
Rescued attachment tech0015f.jpg

brynhamlet - 28/3/08 at 06:24 PM

Wow 'britishtrident' thanks for the info - but it has a head set up for unleaded and a modified electronic dizzie. Neverless I appreciate your advice and have stuck it in my help file for future reference.
As for the earth problem. Got home, got changed, straight into the garage, stuck a jump lead from the battery to the starter and hey ho of the engine did go.
New earth lead tommorrow, just fix the radiator and off we go go.