Weak engine.. where is the issue?

73SpeedBuggy · Post by **73SpeedBuggy** » Wed May 30, 2007 4:12 am

My buggy's engine can barely keep it above 50mph when going up hill. It takes forever to even get to 50mph on a flat grade. I've replaced the sparkplugs, sparkplug wires and coil. Adjusted the idle, timing and point gap. I tested the compression and had some odd results. The two left cylinders test right around 100psi, but the two left test at 120psi, which makes me suspicious as that's way to high for an engine I know hasn't been rebuilt in some time. THe only thing I haven't done is adjusted the valves as my current exhaust blocks the valve covers and looking at the exhaust studs I'm betting most of them are going to break off when I try to remove the exhaust. Could the valves being out of adjustment really be causing this much loss in power? Any other thoughts? THis is on a stock 1600 dual port with a 34 PICT.

newmanx59 · Post by **newmanx59** » Wed May 30, 2007 11:41 am

The valves should be the first place to start.

joemama · Post by **joemama** » Wed May 30, 2007 5:50 pm

I would make sure the advance is working on the distributor. Hook up a timing light and see if the timing advances when you rev up the engine.

73SpeedBuggy · Post by **73SpeedBuggy** » Wed May 30, 2007 6:58 pm

[QUOTE="joemama"]I would make sure the advance is working on the distributor. Hook up a timing light and see if the timing advances when you rev up the engine.[/QUOTE] Yeah, it's advancing. I set the timing with a light at 3500rpm as per these instructions: http://www.vw-resource.com/tune-up.html#timing . I believe I have an SVDA distributor as it advances without the vacum hose hooked up and as per these instructions I set the timing to 30Deg. BTDC at 3500rpm without the vacuum hose attached

Lee · Post by **Lee** » Wed May 30, 2007 9:39 pm

What size rear tires do you have? What gearing does your transmission have? Swing axle? IRS? Do you have the Dual Cannon exhaust (that's the type that typically blocks the valve covers. It also robs the engine of power).

73SpeedBuggy · Post by **73SpeedBuggy** » Wed May 30, 2007 10:33 pm

[QUOTE="Lee"]What size rear tires do you have? What gearing does your transmission have? Swing axle? IRS? Do you have the Dual Cannon exhaust (that's the type that typically blocks the valve covers. It also robs the engine of power).[/QUOTE]. I have 15" rims, not sure what the tire profile is, but they're not huge. AS far as I know the transmission gearing is stock and this is with IRS. Here's a pic of my exhuast: http://memimage.cardomain.net/member_images/12/web/2088000-2088999/2088705_13_full.jpg . Ignore the stupid mudflaps and stock beetle tires, I was trying to get it to pass Pa inspection when that pic was taken.

Lee · Post by **Lee** » Wed May 30, 2007 11:15 pm

The size should be listed on the sidewalls of the tires. I run P235/75R15 and the stock 1600 didn't pull them too well up hills with the stock gearing in the IRS transmission. I ended up with a lower ring and pinion (4.37 from 4.12) and a lower fourth gear (1.00 from .89). Now I can climb hills pretty well with the stock 1600! The dual cannon exhaust is known to has less power than any merged system, but you already know that from the other thread!

90volts · Post by **90volts** » Thu May 31, 2007 2:58 am

yep, try the valves. i was losing power with mine. didn't check copression, but when i puled the plug off it didn't bog down, just made like it didn't miss a beat. my exhaust valve was too tight or loose, don't tremember which, but after the adjustment it started working properly.

73SpeedBuggy · Post by **73SpeedBuggy** » Thu May 31, 2007 11:32 pm

[QUOTE="90volts"]yep, try the valves. i was losing power with mine. didn't check copression, but when i puled the plug off it didn't bog down, just made like it didn't miss a beat. my exhaust valve was too tight or loose, don't tremember which, but after the adjustment it started working properly.[/QUOTE] Yeah I noticed I could disconnect 1 plug with no noticeable change in idle and even two with very little change. Is this a sign that it's way past time for a valve adjustment? AS for the reason I haven't done that yet, I've been told I should try to crack the nuts holding the exhaust on with a chisel in the hopes that I can get the exhaust off without snapping off the studs. Has anyone done this?

fubar · Post by **fubar** » Fri Jun 01, 2007 2:21 am

When things are siezed up soak them in penetrant, shock them with a hammer, and heat. What would happen if I did it would be the very last stud would snap off in a spot where a drill and easy out would not be an option....Did the car pull 4th gear before ?or has it always been sluggish? Even with a bunch of HP the gearing has to be right.

90volts · Post by **90volts** » Fri Jun 01, 2007 3:06 am

[QUOTE="73SpeedBuggy"]Yeah I noticed I could disconnect 1 plug with no noticeable change in idle and even two with very little change. Is this a sign that it's way past time for a valve adjustment? AS for the reason I haven't done that yet, I've been told I should try to crack the nuts holding the exhaust on with a chisel in the hopes that I can get the exhaust off without snapping off the studs. Has anyone done this?[/QUOTE] well, it's def a sign that somethiing is wrong. if it 's an old engine, maybe time for a rebuild. but mine only has about 1500-2000 miles since rebuild. turned out being a valve tht needed adjusted (thankfully).

73SpeedBuggy · Post by **73SpeedBuggy** » Fri Jun 01, 2007 1:13 pm

[QUOTE="fubar"]Did the car pull 4th gear before ?or has it always been sluggish? Even with a bunch of HP the gearing has to be right.[/QUOTE] I just got it on the street last month after purchasing it in Sept. of '05, so I don't really know if it's ever had any power in 4th or not.

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Weak engine.. where is the issue?

Weak engine.. where is the issue?

weak engine