Mark Maras

@jalexquijano If you'd like someone in Panama City to check out your carbs there's a JDM shop there. Also, look into any British or Volvo repair shop that has an older mechanic. Volvos used Hitachi SUs (I think) and any older British mechanic should know SUs inside and out..

Well, I can't imagine why a stock cam wouldn't work. It might not be the first choice but it would certainly work. I think more compression tests (wet, dry, plugs out, throttle wide open) are a good idea. Fresh #s may show something new. I'm curious if you have any theories as to why more plugs are fouling now when it was only #4 in the past. Be sure to try the downhill 4000 RPM throttle-off test. It may provide a clue if there's oil consumption.

It appears you've got the carbs balanced. The mixture screws at the bottom of the carbs are the secondary mixture adjustment. The primary mixture adjustments are the float levels. I'd check those next. They don't have to be exact, just close.

Nine years you've been dealing with these problems. Were all the valve seals replaced and did the problem get worse (more plugs fouling) after that?

@jalexquijano Last year, as I recall, we were dealing with #4 plug fouling. Now it appears the problem has spread to all but one cylinder. What has been done to the engine since then? Were all the valve seals changed? Next time you're out driving find a nice steep hill, drive down the hill with the engine at around 4000 RPMs, and take your foot off the throttle pedal. Watch in the rearview mirror for blue smoke. Tell us what you see.

I ran into this problem of the engine hitting a wall. I was on the freeway when the car slowed to 45 mph, Wouldn't go any faster regardless of which gear it was in. It would free rev to 6000 with no load. It turned out to be a partially plugged fuel filter. The fuel pressure (mechanical pump) was fine but the fuel volume was restricted. Have you tried a fuel volume test along with the pressure test?

@jalexquijano Was the engine running worse back in March and was it still fouling one plug? Now it seems to be worse. All but one plug shows fouling. Random question, does the engine use a lot of oil?

I'd do another compression test (wide open throttle, all plugs out) before I opened it up. My thought is if it's got good (enough) compression, it's got to be fuel or spark.

I'd start by cleaning it up, remove anything that's loose, and then go at it with a wire brush on an angle grinder. Once that's done poke around any suspicious areas with an ice pick. That will tell you which areas are thin.

I've always coated both sides with a thin layer of grease. I've cussed every paper gasket I ever treated with grease, but it was always when trying to remove it later. Never any leaks.

It eliminates air restriction to the cylinders. That results in a faster cranking speed. I've never done a C test without removing the plugs but I'm guessing it wouldn't affect the numbers more than a few psi.

Did you pull all the spark plugs first, Turn it over until you had oil pressure, and hold the throttle wide open during the test? The 140 on the fourth time around was probably because the engine was getting oil pressure.

They make new crush washers?

Any good contact adhesive will work.

As long as the front and rear angles are the same or darned close.

A bit off-topic but in the past I've usually attributed an engine that "hunts" to be caused by a lean mixture.

We DEQd an 81 RX7 many times in Portland. They could care less about looking at the engine. The first time took a few carb adjustments and trips through DEQ but the entire crew gave us a cheer when we succeeded. Maybe they were just glad to see us go?

Clockwise and counterclockwise adjustments are made imagining you're viewing the bottom of the carb. Try reversing the adjustment directions.

@jalexquijano Have you checked this?

The only time (in twenty plus years of spirited driving) I ever experienced an erratic misfire at high RPMs was cured with a new set of BP6ESs. My experience with a partially plugged fuel filter resulted in the car refusing to go above 45 mph in any gear but would freely rev to 6000 rpms under no load.

I had a friend sit on each front corner as I tightened the bolts.

It will pull high RPMs under no load. What happens when it's under load? Does it start to miss intermittently or just run out of power and refuse to rev higher? While not ruling out electrical, I'm leaning (snort) towards it being a lack of fuel.

I agree. Use one set of points. The plus side is you won't have to carry a spare set in the glove box.

I vote for polish and clear acrylic paint.

I believe the fender bolts that are now interfering with the hood are supposed to have a shorter head than ordinary bolts.