harvs ek 327 wagon

[Blacky]

[Harv]

Some time back I had a low-speed miss in the wagon, and a rough idle in drive. I hunted madly for an air leak, and found nothing. I figured the PCV had stuck open, and my fiddling had let it reseat. All good.

Damn miss came back, and got worse. Nasty firing up through the carb (leaning out on acceleration), and surge at low cruise. Inside of the carb now black with soot. Spent quite some time trying to hunt it down, to no avail. Car drives fine with my heavy right boot into it, not so good when Driving Miss Daisy.

Admitted defeat, and called the bloke who did the dyno tuning on it a few years back. He hunted through the same stuff I did (air leaks, coil output and resistance, timing etc) and found nothing. Noted though that the carb is drawing vacuum (when first accelerating) without any fuel response. Suspect that the carb has an internal air leak. Carb is a early 2000's Holley 600 vac secondary, with internal float adjustment. They are notorious for being of poor casting quality (porous), as Holley had offshored their manufacturing. Apparently the internal leaks show up the way mine has. Carb cannot be rebuilt-to-rectify due to the porosity. I'm always a bit suspect when the answer is "replace the parts", so did some Googling, and appears legitimate.

Plan is to replace the Holley with a QuickFuel carb. Owned by the same people as Holley (and very similar design) but far better quality. Carb is on order, will see how we go.

As an aside, its not a good idea to do a compression check with my small gel-cell battery. Tested the passenger's bank (1, 3, 5, 7) and all around 185psi. Moved to the drivers bank and 2 was fine, but 4 and 6 were around 160psi. Couldn't test 8 as I was on my own and can only use a push-in tester on number 8 due to the steering shaft (can't use my normal screw-in compression tester). Crapped myself, thought I had killed 4 and 6 (leaky inlet valves mebbe blurting up into the carb). Got the leak tester out (should have started with that instead of the compression test), and rechecked 4. Had a hard time holding the crank still, very little leak down. Same on 6. Hmmmmm.... Dawned on me that 4 and 6 were the last I compression tested, and mebbe the battery was tired (still turned over well). Retested 4 and 6 with a fresh battery, and they too are up at 185psi. All good, no major surgery needed on the head or bottom end.

Cheers,
Harv

[Errol62]

Phew. I hate testing compression when the fitting isn't screwed I properly and comes off with a bang.

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[Harv]

That Chev was never meant to be in that skinny engine bay. I get the plug out, then try to screw the compression tester hose in. The hose ends up bent against the inner guards. As you turn the hose to start the thread, the bent hose fights you all the way... what should be a 30 second job becomes a five minute fight per cylinder. Painful.

Cheers,
Harv

[ardiesse]

Harv,

Compression-testing is not that much easier on two-door Holdens which came out with SBCs as standard equipment . . . particularly numbers six and eight spark plugs.

Rob

[Errol62]

Always on time in a 179........

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[gledge]

As long as ya cam doesn’t f##k itself


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[Errol62]

true…..


FB ute fixer upper, EK van on rotisserie

[Stygian]

Suspect that the carb has an internal air leak...They are notorious for being of poor casting quality (porous), as Holley had offshored their manufacturing. Apparently the internal leaks show up the way mine has. Carb cannot be rebuilt-to-rectify due to the porosity...
Cheers,
Harv

I had a similar problem with the first Stromberg on my triple grey set up. Fuel kept dripping from the main jet plug onto the intake manifold, even though I replaced the copper O-ring twice (being VERY careful not to overtighten) and all gaskets in the carb once. Got a spare Stromberg body from a mate, cleaned it up, lapped the top, took all the components out of the old carb and fitted them into the replacement body, complete with a new overhaul kit. It has never leaked since and manifold vacuum increased by 3" Hg.

[Harv]

I pushed my luck just that liiiiiiitle bit too far...

The wagon had been missing off-idle, but once my boot was in to it there was no issue. With the problem diagnosed as a crook Holley, I bought a new QuickFuel carb. Carb arrived before Christmas, but had only half a day to pack the camping gear, fit the carb (including making new fuel lines) and get it working. Car needed to do a 1200km run (Sydney/Tamworth/Taree/Sydney) with the trailer, and the idea of running an untuned out-of-the-box carb that far seemed foolish (just my luck to run lean and melt the pistons out of it at highway speed).

Had a chat to the dyno tuner, and we figured the issue would get no worse (famous last words). A slight stumble off-idle won't damage much, and the 1200km were mostly at highway speed. Left the QuickFuel carb in its box and figured I'd do it after Christmas.

Packed up and headed off Christmas Eve. Made Tamworth fine, though a little damp (despite much fettling, the rear door on the wagon leaks). Great Christmas day, then hit the road again Boxing Day bound for Taree. Went the long way round (via Hexham) as fuel is a little scarce going the direct route (and the wagon is somewhat thirsty ). Car ran fine until Raymond Terrace, then struggled pulling out of the roundabouts on the north side. Got it up to 110, started loosing power, then a series of lean misfires followed by rolling coal. Rolled to a stop, did the obligatory check under the bonnet (yep, engines still there ), gathered my thoughts and started again. Got 5km up the road and same result - no power, lean misfires and a smoke screen to hide my shame behind. Clearly the carb problem was worse.

Managed to roll into a rest stop (nicest place I've ever broken down). Figured lean misfiring at freeway speed is a great way to turn forged slugs into tiny, sparkly fireflies out the exhaust so called it quits. 600km into a 1200km trip . Tilt trayed it to Taree, parked it under a tree at the campsite under a car cover and ignored it for a fortnight. Tilt trayed it back home again last weekend.

Converted the QuickFuel from electric to manual choke, split the fuel line for the dual fuel bowls. Old carb off, and slight mystery found. Looks like a short piece of round plastic, tapered each end, was present in back vacuum channel. Manifold vacuum is taken from under BOTH butterflies, goes out via two channels cut in the carb base, and exits the carb in a neat pipe at the carb rear. The plastic bit was in only one channel. The gasket marks show it was jammed in one spot. Its not big enough to fully seal the channel (and why the hell would you want to anyway)? Anyone ever seen something like this? It's been there since the engine was built, but no idea what it is. Pretty confident it is not the source of my woes, but got me curious.

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New carb on and plumbed up. Fired up first attempt, lovely and crisp. Responds like a fuel altered, like it did when first built. Will tootle it around a few days, get it dyno tuned again then take it to Eastern Creek for some leaning-on.

QuickFuel carb.jpg (870.4 KiB) Viewed 1133 times

Cheers,
Harv

[EK283]

Not sure where that plastic is from but vaccuum does play havoc if its not right with the carby.

I should have ordered heads with the angled plugs as well, a mistake i will have to live with !!!

Off the topic, im going to bin my Gemini booster and by the looks of it you still run one, do you want it ?

Regards Greg

[gledge]

Have a look at MSD spark plugs if you have clearance issues as the make shorter porcelain plugs


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[Harv]

Off the topic, im going to bin my Gemini booster and by the looks of it you still run one, do you want it ?

Thanks for the offer (appreciated) but I am ok - have one spare one on the shelf if I get in trouble.

I’ll live with the booster for now, but would never use the Gemini booster with a lumpy cam again - reservoir is waaaaayy too small, leading to vacuum tank and pump shenanigans.

Cheers,
Harv

[Harv]

The source of that bit of plastic has been bugging me, so I asked a question over on the HAMB. Some good feedback - it is likely that the item is not plastic, but ceramic. It is probably a piece of ceramic media used in a vibratory bowl to deburr and polish diecast parts.

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Pretty good chance that the carb parts were polished by Holley, the ceramic piece got lodged in the channel in the carb, and never noticed when it was packaged then sold. Kinda reinforces that Holley's QA/QC was patchy in the 2010's. The engine builder missing it is not out of the question either given some of the other issues I had, like the early main bearing failure and stuck-on oil filter.

Cheers,
Harv

[EK283]

Thats interesting Harv,

That old carby probably will run fine now the blockage has been removed.

You've had some curve balls thrown at you with this thing thats for sure.

Regards Greg