Folks. You might remember the blue 1.7 in Hull that was on 'the bay' advertised as a serial killer's car, etc, etc, for half-a-larf. Well I think I might have found its dark secret because it won't start when the engine is hot. It starts fine from cold but when its hot the starter motor tries to turn over but it struggles and sometimes doesn't turn at all. I checked all the connections and even replaced the starter motor today and the new motor, though better, still can't start it when hot. Does it just need some Redex and carb-cleaner in the plug holes or is it likely to be anything majorly massive?? Could anything else be making it stick when its hot?? What's the most likely cause?? Is there something better than Redex??

Check the positive battery cable, my 1.7 had this issue where the resistance of the cable would increase when hot - failing to start the engine. Leave to cool and she fired right up.

That is a possible. If the engine is actually getting tight rather than starter issues then the most likely cause is the engine over heating. If overheating you would feel the engine drop in power when hot.

And check the earth strap, I have had the same as Speedy but on the connection from block to battery.

Evil ideas. I'll dig out the multimeter and check the hot and cold resistances tomorrow. I did sand-paper all the connections and re-tighten them all incl. rubbing-off some new paint at the battery end of the earth connection but its possible there's a hidden problem with the live cable connection to the battery or the wire itself. The engine runs absolutely fine - there is no sign of overheating or lack of power when hot. The fan always comes on when needed and the temperature gauge stays steady at about the half-way mark. This one has done about 58k without much use in the last couple of years and only 10k in the last 10 years so maybe the problem has been sitting around for a while!

One further thought and question is that when my 1.4 was hot and I turned off the engine, the electric fan would come on and run for a few minutes. This one does not seem to do that i.e. if the fan is running and you turn the engine off, the fan goes off too. Is that a problem??

Nah, not sure why that's the case as mine would come on after I switched off. But cooling the rad while the car has stopped pumping the water round is a bit pointless tbh. It just does it because the temperature raises slightly as the you've just pulled in somewhere and the airflow has stopped.

Evil ideas. I tested the resistance on the red lead to the starter motor and it doesn't change when the engine is hot but in my density I forgot to check the earth lead resistance although I doubt there's a problem there because I sand-papered that one up like mad at both ends. So yes overheating, overheating it could be?? Perhaps time to change the thermostat (guess its never been done in 23 years) and while I'm at it also put some penetrating oil in the cylinders for an overnight soak?? Also, can you listen to this....

https://soundcloud.com/bogbasic/volvo340

.... I am getting a bit of a whining bearing type of sound ever since I changed the cam-belt. Duh, any ideas on wots going on here?? This was recorded about 2 inches from the cam belt cover so it sounds worse than it is, but any clues much appreciated.

P.S. I did change the tensioners, too.

P.P.S. Duh, hopefully the link to the sound file will work now.

Help, weep and cry. I sprayed some carb cleaner into the plug holes and poured some penetrating oil in after turning the engine over a few times then left it to chillax overnight. I also changed the thermostat and the antifreeze and checked the electrical resistances to the new (!) starter motor, etc. The next day it started from cold and drove absolutely fine but if I stop the engine when its hot and wait for say 30 seconds or so to let it get to about the hottest temperature it will go to, it still partially seizes up i.e. the starter motor turns over so slowly if at all and it won't start. My plan is to spend a few more weekends dribbling oil and carb cleaner into the cylinders and just see if it gets better with driving it about (when its not seized up) - I'll try to go a bit further and faster next time. Is this a lost cause or am I on the right lines or could it be something like shell-bearings which I've read about, heard about, etc, etc...?? Could the oil be too thin - it is pretty thin-looking oil??!!

It could be worth giving it a oil change and engine run engine flush through before you drain off the oil.

To confirm if it is the engine tight or a starter issues have a feel of how hard the engine is to turn over by hand when cold. Then when the engine is hot and the starter is struggling try it again by hand. If the engine turns over the same by hand you know the problem is power to the starter, if the engine will not turn by hand you know it is the engine going tight.

Ditto what Dai says. Whip the plugs out, feel how loose it is when cold.

When you get it hot, plugs out again, try again. Something in the back of my mind says this isn't getting tight, it's something else.

Awesome ideas, I'll pop in some engine flush and take it for a run for a few miles, hopefully without stalling it (!) and then see what its like with new oil. The old oil is clean as a whistle - probably because this car hasn't done any miles at all since the last oil change, except maybe a few gentle shopping trips in Hull.

Talk about volvo owner with 0% brain function - I did exactly as above and its sorted. Car starts perfect from hot!! I was 90% sure it wouldn't but it did reproducibly start multiple times from hot. Awesomeness abounds.

Just got to sort out that whining noise which is still there. Any more ideas?? Cam bearings, belt too tight?? I'll get the part number for the new belt asap...

Sounds like the belt is a little tight.

Try to use the recommended Volvo setting tool - I've found it easy to over tighten by using the 1/4 turn method - but perfect every time using the reference beam and plunger.

Other possibility is aux belt tight and it's one of the alternator bearings complaining.

Mac.

Folks, this is what I don't understand because I fitted the new belt (which is a Dayco 94126 - that's the correct one for 1.7 engine, I believe) and it was so tight when it went on (I had to use all manner of trickery just to get it to slip over the tensioners and I knackered one belt in the process), there was no scope to adjust anything.... it was a battle to get the tensioners on and when they were on, the belt was so tight (well, you could turn it through 45 degrees each way in the longest gap between pulleys) that I just hoped it would be OK. As for adjusting the tensioners, they were right back at their loosest setting and any adjustment would have been nutty to attempt with the belt already so tight, is Dayco sh*te?

Are you sure it's the correct belt???

Are you trying to fit a 124 tooth belt to a car suited to a 125 tooth belt - see
viewtopic.php?f=39&t=6164

Mac