|
In any case two seconds of cranking is a satisfactory
time for an engine to start. Not sure if you intended this
to be taken literally. Also in the subject you say that
sometimes it is slow and others it is fast. If this refers
to the actual cranking speed, Humberto may be right
in pointing you to voltage and starter brushes. Another
area to check is the connections on the big cables from
the battery, both the hot one and the ground one.
Because of the large currents these carry, any small
resistance can make a big difference in cranking
amperage and thus starter torque and speed.
Another link in this chain is the starter solenoid.
In spite of the fact that I have 3 Volvos all over 26
years old I have never bought a new starter or
solenoid. I do have a couple extra starters that
I have re-brushed and cleaned the contacts on
the solenoids several times each. Once you get
the solenoid apart it is easy to clean the contacts
and they can be built back up using silver braze
alloy ("silver solder") by a competent torch operator
at little or no cost. The key to this is getting the potting
off the plastic cap of the solenoid so you can take the
two screws out that hold the cap on, unsoldering the
wires to the solenoid coil that are in hollow rivets in
the cap, then getting the funny washers off the contacts
(which are like 8mm bolts with copper heads) so you
can get them out of the plastic cap to work on them.
They will usually have black, shallow pits on them that
can be easily filed out, being CAREFUL to keep them flat.
Same is true of the moving contact. After about 3 iterations,
you'll have to build them up with silver braze alloy but that
will probably be several years off. After you get the contacts
clean, put them back in the way they came apart, guide the
wires into the hollow rivets (remembering which one had
the double wire), re-solder the wires and reinstall the cap
with the two screws. Then put the funny washers and nuts
back on the contacts and put the solenoid back on the starter,
being sure the nuts holding the battery cable and the lead
to the starter motor are good and TIGHT (and clean!)
This effort is particularly indicated when the starter clicks
instead of cranking. After a few times around you should
also take the starter motor apart, check the internal wiring
and the brushes. Clean the commutator with about 240
grit if it is smooth but dark. Otherwise you may need to
take it to a shop and get it turned (if it has grooves in
it or is badly pitted). You will probably find that starters
resist disassembly pretty strongly, especially the big
flathead screws in the side. A normal screwdriver
will usually not do it. I generally use a 3# hammer and
a punch at one end of the slot to persuade them.
Allen head flathead screws would be a really great
replacement item here. They are metric, unlike most
of the rest of the parts on my oldtimers.
Hope this is helpful. Don't wear nice clothes to
do this and don't try it on your wife's kitchen table!
|
