Hi

I recently overheated and warped the head on my sj413jx.

I have so far replaced:

- head gasket ( and planed the head)
- rocker cover, intake and exhasut gaskets
- A couple rockers (beacause the internal tappet threads were ruined)
- water pump
- timing belt & tensioner

I have got it running sweet now and it starts well when engine warm, but she only starts (cold) when the starter motor cranks really fast. Ie when the battery is jumped from another vehicle.

Any suggestions as to why it doesn't start well when cold?

The choke works fine.

Sometimes on the third or fourth long attempt it will start and it seems to prefer starting without much throttle or choke.

Might be a timing issue?  Are you using a manual choke or the automatic one?

I dont think its timing.

I have set it according to the haynes manual and it sound like it's running good once started.

Would putting less timing advance help for starting?

Using a manual choke by the way

The fact that it has to crank over quickly is interesting.  Usually that will only happen if you have a weak spark or something similar.  I was asking about timing because if your timing is advanced to far your engine has to have enough speed to overcome the fact that the engine is firing to early in the compression stroke.

New plug wires cap and rotor I assume?

no i haven't changed dizzy cap or wires. maybe i should.

more bad news today. It started making a hideous vibrating noise when driving. Kind of like when your straining in too high a gear but much worse. it started only at the front but then went to the rear too. I thought maybe wheel bearing but then why both front and back? it didn't seem to depend on engine rpm and came and went in a kind of random way.

its still doing it. Any ideas?

vibrations are probably coming from loose drive shaft or bad ujoints....they can cause some major vibes. I lost 3 bolts on the front and the other got loose and it was crazy loud.

As for the engine starting hard. Get a compression tester and check the cylinders. I'd say you got low compression is 1-2 and that is why it'll start when hot and not when cold...unless you crank hard and fast.

We had a dirt bike and you could crank all day with no luck...slap it in second gear and push it and it'd fire right up in a about 30 seconds of hard pushing.

Don't forget to check the little drive shaft...it's a pain to get out but it can cause some major vibes

lets take a look at what the cold compression is.

the typical 8 pumps with the throttle open should net you 80 0/0  of what the hot #'S are.

this may expose some piston / ring issues damaged in the o heat

I found the front wheel bearings had a lot of play. I just need to find a big enough spanner to get the lock nut loose.

I think low compression sounds like it could be it. I can now start without jumping it, but it requires turning the engine over for two or three long attempts.

As for the compression test i had already checked it and i cant remember the exact figures but the were on the lower end of what was considered acceptable according to the haynes manual. One came out slightly below the minimum.

I think they came out around 170psi with a range of about 20psi.

Would this be low enough to cause starting troubles do you think?

WERE THE TESTS  DONE COLD. 170 SOUNDS OK, BUT GAUGES VARRIE LARGELY IN ACCCURACY. HAVE YOU EVER USED IT ON A KNOWN GOOD VEHICLE? LOOK FOR 180 TO 220 AS AN AVERAGE HOT TEST, 8 PUMPS THROTTLE FULLY OPEN.

I THINK IF YOU DRIVE YOUR SAMMY, SHUT IT OFF, LET IT COOL COMPLETELY OFF (6 + HOURS) PULL ALL PLUGS AND INSTALL GAUGE AND GIVE 8 HITS WITH THE THROTTLE OPEN YOULL GET SOME 40 - 60 PSI #S.

ALUMINUM ENGINES DONT RESPOND WELL TO OHEAT.....

TIME FOR A 1.6 16 V SWAP!