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Charging circuit question

Radtap said:
Also compare the pulley size between your new and old alternator, if you got a denso you'll need shorter belts, 10x920mm iirc. Always buy the alternator/water pump belts in pairs otherwise one may be looser than the other, belt wrap sucks on the alternator so you need everything you can get.
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My alternator didn’t come with a new pulley. I’m using? What look like originals. But good tip on the belt length. I’ll check mine.
 
Jill_ski said:
Well I have it to spec.. but he says it’s still too loose. Which makes me think I should probably see if I can find a pulley. I’ll try tensioning it when it’s cold. And see what happens. I’ll probably replace the belts too.
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It's loose because you need to replace all of the accessory bushings. Use a poly one for the upper bracket and rubber for the lower two. Your alternator is out of alignment letting the belt slip.
 
dl242gt said:
PS the bushings are cheap on Rock Auto. They have both poly and rubber.
You don't need a new pulley. Just use a piece of scotchbrite pad to scratch it up ro remove the belt glazing.
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Thank you! I will be stuck in my corporate life until at least wednesday. I will try this for sure. I got the belts from FCP euro. they got here faster than I expected. Ill get some bushings for the job as well! i really appreciate it.
 
Great news everyone! I have a positive charging circuit. New belts and bushings for my alternator and we are in business.

Unfortunately now I have a terrible idle. And it shakes like it owes me lunch money, despite just changing the motor mounts. Sooo on to that issue.
 
It's OK you have to take care of these things one at a time. A shaky idle can mean several things. On a 79 kjet car vacuum leaks are a common cause. The injector seals leak air into the engine and the intake manifold gaskets decay and cause air leaks into the engine. I would also check the smaller vacuum lines like the ones going to the charcoal canister. The ones going to the control pressure regulator are important for good cold engine performance so be sure to check those as well.

If all that checks out I move to the engine mixture by checking the dwell and also putting a voltmeter on the O2 sensor if something is fishy with the dwell setting. You need a duty cycle or dwell setting on your multimeter to check the dwell setting.
 
dl242gt said:
It's OK you have to take care of these things one at a time. A shaky idle can mean several things. On a 79 kjet car vacuum leaks are a common cause. The injector seals leak air into the engine and the intake manifold gaskets decay and cause air leaks into the engine. I would also check the smaller vacuum lines like the ones going to the charcoal canister. The ones going to the control pressure regulator are important for good cold engine performance so be sure to check those as well.

If all that checks out I move to the engine mixture by checking the dwell and also putting a voltmeter on the O2 sensor if something is fishy with the dwell setting. You need a duty cycle or dwell setting on your multimeter to check the dwell setting.
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Would the injectors leaking air be something that would even out at about 900rpm? Mine is idling roughly but when I give it gas to about 1k rpm it sounds healthy.
 
Jill_ski said:
Would the injectors leaking air be something that would even out at about 900rpm? Mine is idling roughly but when I give it gas to about 1k rpm it sounds healthy.
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As the engine revs up. The amount of air leaking becomes less compared to the overall amount of air. So it seems to even out. But if they are leaking air into the engine it is still happening. A vacuum leak with kjet at idle can make what seems to be a miss. If the last time the injector seals were replaced is unknown then they are due for replacement. N/a cars they last about five to seven years. Turbos less. I would also consider an intake gasket.
 
Another sneaky spot for vacuum leaks is the PCV system. On my old K-jet Volvo, the breather box was split/plugged and the hose up to the intake was all brittle and cracked.
 
dl242gt said:
As the engine revs up. The amount of air leaking becomes less compared to the overall amount of air. So it seems to even out. But if they are leaking air into the engine it is still happening. A vacuum leak with kjet at idle can make what seems to be a miss. If the last time the injector seals were replaced is unknown then they are due for replacement. N/a cars they last about five to seven years. Turbos less. I would also consider an intake gasket.
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I will look at getting some. I’d say it’s entirely unknown.
 
billkaz said:
Another sneaky spot for vacuum leaks is the PCV system. On my old K-jet Volvo, the breather box was split/plugged and the hose up to the intake was all brittle and cracked.
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I was referencing the green book and I saw this hose. I’ll have to look at mine. Thanks for telling me!
 
dl242gt said:
It's OK you have to take care of these things one at a time. A shaky idle can mean several things. On a 79 kjet car vacuum leaks are a common cause. The injector seals leak air into the engine and the intake manifold gaskets decay and cause air leaks into the engine. I would also check the smaller vacuum lines like the ones going to the charcoal canister. The ones going to the control pressure regulator are important for good cold engine performance so be sure to check those as well.

If all that checks out I move to the engine mixture by checking the dwell and also putting a voltmeter on the O2 sensor if something is fishy with the dwell setting. You need a duty cycle or dwell setting on your multimeter to check the dwell setting.
Click to expand...
How is this looking for my cam? I haven’t got a frame of reference for Volvos only Mazdas. 350k miles. Anything you’d suggest while I’m in here?
 

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That looks fine to me. The head has been off before, those are later head bolts.

Edit: may as well check valve clearances but the caveat is the old hushers make getting an accurate reading tough.
 
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