What broke now?

[510_dreamin]

My 510 recently started to have some odd issues. A couple of weeks ago all was well, and was running the best it had been since I've had it. For reference it has an L20, dual webers, stock ignition. 

 

On Monday I fired it up, and it was backfiring and popping alot. Made it a few blocks and drove it home it was backfiring so bad/loud. 

Today it started fine but was really down on power, and anything more than 15% throttle a crackling sound was coming (it only used to crackle at WOT, foot to the floor). Drove it a couple miles to cars and coffee, and then on the way home, it started to smoke a bit (white-ish) then seemed to stop when I get home.  Its had a pretty decent oil leak for awhile. Not leaking any coolant however. 

 

I am thinking maybe a bad distributor/ignition? Should I upgrade it to a pertronix system, and if so what parts should I look in to?

 

Any ideas what may be wrong with it? It will be a few weeks till I can get it to my mechanic so hoping for some insights. Thanks!

[datzenmike]

I suspect a bad head gasket. If white exhaust it may be steam from coolant. Lack of power can also be that. It may not have any obvious external leaks but check the rad level. If it needs topping up it could be the gasket.

 

Though not proof, if you pull the plugs and one is suspiciously cleaner than all the others it can be from the steam cleaning it. It may also have coolant on it and be wet.

 

 Keep an eye on the rad level.

 

 

If pre prepared and ready, this is a morning or afternoon fix and will cost you the price of a head gasket... about $30

 

 

[510_dreamin]

Coolant level is good and oil level is also good. Which is concerning about oil level because I haven't added any and it doesnt seem to be going down.

 

Head gasket replacement isnt too bad of a job?

[datzenmike]

Oil level is unlikely to be affected by a bad head gasket.

 

Keep checking the coolant level. If it doesn't go down it may be something else. I'm basing this on your comment about the white smoke.

[banzai510(hainz)]

this is me trouble shooting here.

I have Mikunis Solex and the jet blocks would back out and cause a bogging issue when I really give it the gas.

Also 1 time the tunnel venture funnel thing was loose inside causing a high speed cut out. I tighen it up where it wouldn't wiggle and was fine after that.

 

As for ignition make sure the points are good and you use a stock coil and ballast set up. So if a coil or anything was changed we need to know. as resistance values do matter as points don't like a lot of current.

Use a timming light and see what you get.  I would adjust 12-14 with dual carbs.

 

also make sure you valves are adjusted correctly not that its the case but I would drop a lash pad once in awhile but it more or like runs on 3 cylinders

 

I don't think its a Head gasket

Edited February 19, 2019 by banzai510(hainz)

[510_dreamin]

Thanks l'll check out the timing this weekend. It was running as good as it had since I got it and when I started it up and it started backfiring, I really got nervous. 

 

So theres no need to upgrade the ignition from the stock set up?

[datzenmike]

Well the later '79 Matchbox eliminates the points and has higher output. You never have to change or adjust or clean points again.