Spark Plugs

[SaxMan]

After dealing with dozens of distractions (all good distractions, mostly related to bicycle stuff and some of my writing / historical research) that have kept me away from my Sprite (and from BCF, for that matter), I finally pushed everything aside and said "It's time to work on the Sprite". Nothing crazy for the winter maintenance, just a general going through everything to get it ready for another season of Dad / Daughter adventures.

I pulled my plugs to replace them. Cylinders 1 & 2 had rather normal looking wear on the electrodes, although there was carbon around the ring. Cylinders 3 & 4 were more sooty on the electrodes. All were a little bit oil fouled, but that's been an ongoing issue. I'm thinking the carb mixtures are off? Just not sure what would cause that kind of variation in wear.

On the upside, the Seafoam treatments seem to be helping to keep the motor going until I can pull it and rebuild. Cold compression has moved up 15 psi from 150 to 165 on my low cylinders, and my high cylinders are (1 and 4) are 172 and 168. That may also be me getting better at making the valve adjustments.

 

[NutmegCT]

Seafoam worked wonders on my TR3 engine. I did the "one tablespoon of SF in each cylinder, soak overnight" technique. Got all four cylinders nearly equal in (good) compression.

Assuming you have a single carburetor, have you checked the gap for each plug? And that the plugs all go down the same amount when threaded in? I found one plug on my Nash, which had three (!) washers in the hole, instead of one.

Also, I'd suggest driving about ten miles, up and down hills, and then re-checking the plugs. As you say, you've been away from the Sprite for a while. Crud can build up in lines, which a good drive might clear.

Tom M.

 

[SaxMan]

I have the dual carb setup. I'll hit the cylinders directly with the Seafoam and see what happens. Probably would make sense to pull the plugs for inspection on a regular basis to see where things are going.