Another problem fixed. n - 1 to go.

General_Failure Use your head, don't abuse it!

1,036 posts · joined Jun 2004 · 4 Aug 2006, 4:29 pm

#518850

Hello everyone.

Today I fixed yet another problem which didn't help my 1800 '74 camper run any better.

I keep finding and fixing problems, but it never seems to affect the motor!

Basic symptoms of the motor:

* Strange noise on left hand side of engine.
* Slow to start engine. needs lots of accelerator pumping before it catches.
* Terminal velocity of ~60km/h, yet doesn't seem to have major power issues below that.
* (after todays repair) A perceived vertical vibration of motor. Felt like a misfiring plug, but along the vertical axis.

What did I do today?

I straightened out the interfaces between the heat exchanges and the tailpipe. There was major leakage there.
The repair made the motor a tiny bit happier, and a fair bit quieter.

Problem is I can block off the exhaust (used my footwear) and it doesn't affect it in any meaningful way. So a leak somewhere else. But an exhaust leak couldn't be causing the horrible running, right?

This is a partial list of what I've fixed since (and including) the last major repair:

* Replaced rings
* Replaced 2 pistons
* Replaced 1 head
* New cylinder base, head etc gaskets.
* Fixed inlet manifold head gaskets (I managed to put 2 on one port and none on other).
* Replaced spark plugs
* Replaced burnt sparkplug lead
* Tightened cutoff solenoids (one had undone a bit)
* Replaced some engine bay wires.
* Re-adjusted valves
* Cleaned out carbies
* Fixed vacuum leak
* Readjusted idle
* Did timing
* Tried a different distributor
* Replaced battery
* Swore
* Checked air filter
* Fixed RH accelerator pump ejaculating wildly into engine bay

I think that's most of it. So many things that I came up with that should have affected the problem. None really have.

My next step is to pull off the heat exchanges and check the O gasket things are all there.

Where should I go from here?

I'm thinking checking the vacuum. I'm just not too sure how to do that in a meaningful way.

If at first you don't succeed. Build, build again.
Vehicle: 1975 Special order delivery walkthrough panel based LCA pop-top camper. Motor: Nippon 1.8L Single port Wasserboxer, Transmission: 3 rib 002.

76camper Fahrvergnugen

884 posts · joined Jan 2005 · 4 Aug 2006, 6:09 pm

#518875

Alrighty... where to begin?

The exhaust back pressure at idle shouldnt really affect the engine running, an air leak probably wont rob your engine of power either. (take off all exhaust components it will probably run better!).

engine needs 3 things

Fuel
Spark
Compression

Seeming as you have changed over dizzy, and it was still the same i would rule out spark.

And by the sounds of it the compression isnt too bad. Might be worth getting a compression test. Each pot should be within 5% of each other.

Now the fuel part. I duno the history of your carbs, but it might be worth trying to source a rebuild kit and rekit the carbs or a spare set... even if just to borrow. Maybe go to a vw workshop and ask if you can borrow a set...

how did the big move go? Settling in now?

http://www.bytevision.com.au/dee/kombi/index.htm

kombidaze Slammed & Awesome Dubber

83 posts · joined Aug 2003 · 4 Aug 2006, 6:27 pm

#518881

seems like your've been busy here a just a few of my thoughts
pistons have to be within 5 grams of each other otherwise unbalanced engine,
head gaskets have been known to leak, most rebuilders leave out head gaskets amc heads recommend no head gasket
probably good idea to replace all spark plug leads
solenoid valves can fail causing your starting problem even if they click they can still be suspect you can get just the jet which screws in to replace the solenoid valve,
your carbies would probably do with a rebuild kit put through them, the accelerator pump outlets must point straight down the venturi for best effect if the brass bit is loose you will have problems are the throttle shafts loose? if so they can be rebushed
the valves should be set at .008 both inlet and exhaust do they stay at about the same gap or are any closing up?
there is a possiblity of many vacuum leaks all the rubber hoses should be hose clamped have you checked the rubber hoses that connect up to the brake booster, they can often be perished and cracked
leaking headers not good replace the copper gaskets some people recommend anealing them first look at http://www.ratwell.com/
how good is your muffler? it could be blocked causing lack of power
goodluk (now i'll go back to my kombi which I'm replacing a head, new rings, reconditioned gearbox, repacking cv's etc, etc)

toplessbug Fahrvergnugen

879 posts · joined Aug 2002 · 4 Aug 2006, 8:20 pm

#518906

aquire a vac gauge and a bit of hose and connect it to the balance tube between the manifolds,look for about 17" of vac and the needle should be rock steady,google vac gauge interpretation and study
believe it or not, most engine problems and adjustments can be diagnosed and /or checked with a vac gauge and a carefull analysis of the gauge,, if your cam is stock your vac will be ~=17"

Don't argue with an idiot; people watching may not be able to tell the difference.

General_Failure Use your head, don't abuse it!

1,036 posts · joined Jun 2004 · 5 Aug 2006, 3:26 pm

#518981

76camper wrote:The exhaust back pressure at idle shouldnt really affect the engine running,

fixed the remaining major exhaust leak today anyway. One of the heater boxes went on a little crooked, and slightly mashed the edge of the mating area. A little filing and all was good again. Refitted. A lot quieter now. No performance difference.

Seeming as you have changed over dizzy, and it was still the same i would rule out spark.

Indeed. Swapped it out with my 'spare' temporarily. It works fine but has vertical play, so every time I'd hit a bump, it'd disengage from the dizzy drive. Fine for testing though.

The motor also has a GT40 on it. had very little use. I swapped it out with a standard coil to test. No different.
No signs of arcing on the leads either. They all get 0 ohm resistence when multimetered too.
Tried different points. No different. Different rotors. Same again.

And by the sounds of it the compression isnt too bad. Might be worth getting a compression test. Each pot should be within 5% of each other.

checked it with my handy dandy compression gauge. It's been a while since I checked, but I believe they were all a shade over 110psi.

Now the fuel part. I duno the history of your carbs, but it might be worth trying to source a rebuild kit and rekit the carbs or a spare set... even if just to borrow. Maybe go to a vw workshop and ask if you can borrow a set...

I think the carbs may be the X factor here. I know their history but still strongly suspect them.
not too long before I bought the van, it's engine had been reconditioned. This also included carby rebuilds. Since then, I've had a few problems with them. Most notably serious fouling (cleaneed them and fitted a disposable fuel filter), and bolts not being put back in the top after they had a service at the mechanic.

how did the big move go? Settling in now?

Yeah, sorta. It's a strange neck of the woods here. It's like melb, but somehow not.
Still, much nicer house. And no psychotic landlord. No more nosebleeds either. Yay!

Just doing partials from now on. Not ignoring anyone!

Kombidaze:
When I got the replacement piston I took in one of my others. They checked it for the correct size and weighed it to find a suitable replacement.

I'll check out the solenoid valves.

I agree the carbies probably do need another rebuild. or at very least a couple of new gaskets in them and a good cleanout. Although the jets are clean. Checked them.

The throttle linkages are okay. seem to be adjusted right. I'll give them a bit more scrutiny when I'm redoing the timing (again). I just keep redoing it in case I did it wrong last time.

All the hoses are in functional condition. I replaced some slightly suspet ones recently anyway. All of them are clamped.
Checked the brake booster hose a few times. It was my thought too.
...or do you mean the hoses up front? I haven't looked there since I replaced the steering box.

believe me, the muffler isn't blocked. I can look into the 'in' end and see the 'out' end very clearly.

Toplessbug:

Tell me about vacuum gauges, please. I've been trying to figure out where to get one. the only sort I see are the dashmounted ones. And apart froom being next to useless to me like that, they are way too expensive.
Are there workshop style ones available?

If at first you don't succeed. Build, build again.
Vehicle: 1975 Special order delivery walkthrough panel based LCA pop-top camper. Motor: Nippon 1.8L Single port Wasserboxer, Transmission: 3 rib 002.

Oasis Going alone...

1,806 posts · joined Jul 2003 · 6 Aug 2006, 1:21 am

#519067

Is it just a carby manifold leak? The gasket may have been sucked in partially. Start it and lean heavily in every different direction on the carbies and see if it starts running smoothly holding it one way. If it does, then your pressure is blocking a leak on the opposite side to where you're pushing. Good luck..

"Tell him 'We've already got one'"

76camper Fahrvergnugen

884 posts · joined Jan 2005 · 6 Aug 2006, 7:56 am

#519078

Well definantly sounds like a fuel related problem. I havent worked on a set of these dual carbs and trouble shooting them is by no means easy. Theres plenty of sites on carb tuning/balancing. www.ratwell.com is a good one.

Theres plenty of compression there so i wouldnt think thats where u problem was lying. Keep an eye out for a spare set. For the mean time might be worth considering a rebuild or just a clean out of your carbs.

good to head the move went well mate... hope to see ya round a bit more

Edward

http://www.bytevision.com.au/dee/kombi/index.htm

Samblers Officially Full-On Dubber

236 posts · joined Apr 2005 · 6 Aug 2006, 10:27 am

#519088

Sounds like the problem i'm having with my 1800 at the moment (but worse)... just can't seem to get the last little bit of power out of the bugger!

Have you checked your fuel pump? Your diaphragm may be split or may otherwise have low pressure... just worth eliminating.

What dissy do you have? Rather than time the engine at idle, try timing it so that it max's out at 32deg advance (with the vac. lead off so its MECH advance only)... this would show if your advance is a bit lazy.

Other than that, i'll watch your thread closely for ideas to fix mine, Grrr!

76camper Fahrvergnugen

884 posts · joined Jan 2005 · 6 Aug 2006, 2:02 pm

#519112

hey samblers, does timing engine that way make any diff to the overall running of the engine? I think my mec advance may be a bit lazy.

at what rpm does the mech advance max out at?

http://www.bytevision.com.au/dee/kombi/index.htm

toplessbug Fahrvergnugen

879 posts · joined Aug 2002 · 9 Aug 2006, 8:20 am

#520190

yep that will be fine ,get a dash mounted one,s/h will be fine then a couple of feet(600mm)of vac hose and plug it on the bal tube,it doesnt need to be 100% accurate and you can verify that its close enough by putting it on another engine,there are no elec connections just the bit of hose
http://autorepair.about.com/cs/troubleshooting/a/aa112401a.htm
look here for results of your findings,it would take a week for me to write how to interpret these results(1 finger typing)
As i said absolute accuracy is not vital as long as its near enough and rock steady
google around for other descriptions,all mine are on paper,
A vac gauge will be your best friend when you learn to read the results :beer:beer:beer

Don't argue with an idiot; people watching may not be able to tell the difference.

General_Failure Use your head, don't abuse it!

1,036 posts · joined Jun 2004 · 11 Aug 2006, 2:05 pm

#521207

So many replies 🙂
Sorry I took so long. A little bugger calling himself Influenza beat the life out of me.
I'm still a little stupid from it, so please bear with me.

Oasis:

Is it just a carby manifold leak? The gasket may have been sucked in partially.

Are you talking about the gaskets between the manifolds and the carbies? If so I guess it's possible. I've never actually unbolted them.

76camper:

Well definantly sounds like a fuel related problem.

I'm torn between that and vacuum still. Both can unfortunately have the same symptoms. Not enough vacuum = not enough suck.

Samblers:

Have you checked your fuel pump? Your diaphragm may be split or may otherwise have low pressure... just worth eliminating.

Tried that one a long time ago. Unfortunately it wasnt that. I fitted a known good electric fuel pump from a 2L subie. No difference.

What dissy do you have? Rather than time the engine at idle, try timing it so that it max's out at 32deg advance (with the vac. lead off so its MECH advance only)... this would show if your advance is a bit lazy.

I have no idea 🙂
However I can tell you that it used to work fine. And my spare doesn't change performance when it's fitted either.
When I get a chance, ie next time my daughter is at her grandparents' place I'll have another look at the timing. Two year olds are very curious by nature. She also likes to 'drive' the van. Probably wouldn't be too good if she tried it while it was running.

toplessbug:

yep that will be fine ,get a dash mounted one,s/h will be fine

I'll keep an eye out for a secondhand one and/or call around the wreckers. gauges are expensive little buggers. Moreso if just used for testing.
Hopefully it'll help me get a little closer to the answer to this mystery.

I can understand it losing power (and jamming up) after a dropped valve seat.
I can understand it losing power after burnt head gaskets due to overcompression.
But all of that has been fixed. I just don't get why it's being so stubborn.

If at first you don't succeed. Build, build again.
Vehicle: 1975 Special order delivery walkthrough panel based LCA pop-top camper. Motor: Nippon 1.8L Single port Wasserboxer, Transmission: 3 rib 002.

68AutoBug Beetle Restorer - Experience over 138\% - YIKES --

11,654 posts · joined Aug 2002 · 11 Aug 2006, 3:17 pm

#521215

Hi,
The ignition timing can be a large factor if Your dizzy isn't advancing either fast enough or enough degrees...

32 degrees is maximum advance on 009s...

doesn't matter if its only 30 degrees....
but it could be incorrect....

I had a Mitsubishi L300 years ago and it was always timed and tuned etc...
but One day I did the timing on the wrong mark, and the car went OK...around town...
but wouldn't go up hills very well...
I was talking to a mechanic at work one day and He said Your engine sounds - too advanced - I think it was....
so I checked.... and it was...

a leaking exhaust really seems to affect air cooled engines more than any water cooled ones....

If it accelerates OK then the accelerator pump is working OK... in the carbies...

I'm more in favour of an ignition timing problem...
Check the coil is wired the correct way as they will work when wired back to front... sort of...

The resistance of the spark plug leads....
if they are the original VW wire type....
they should read like touching the two ends of the leads together... a dead short circuit...
This is good....

If they are silicon or whatever....
the long and short leads should have slightly different resistance readings....
depends on what they are made of...
but these types of leads can and do burn out....
check the leads at night to see that there isn't any arcing in the leads....

an engine can idle with all sorts of ignition timing and fuel problems...

Best of Luck

Lee Noonan

- Helping keep Air Cooled VWs on the road - location: SCONE in the Upper Hunter Valley - Northern NSW 320 kms NNW of SYDNEY---

General_Failure Use your head, don't abuse it!

1,036 posts · joined Jun 2004 · 13 Aug 2006, 3:42 pm

#521846

G'day. I think I found a massive hint.
Checked the timing today. Perfect.
However, while I was doing it I decided to put my thumb over the vac advance hose end. When the engine is fast-idling, I could feel the tiniest bit of suction. At idle, nothing whatsoever!

68AutoBug wrote:a leaking exhaust really seems to affect air cooled engines more than any water cooled ones....

Yeah, it does. But unfortunately not really in this case.

If it accelerates OK then the accelerator pump is working OK... in the carbies...

Its acceleration is... bad. I'm still not convinced that the accelerator pumps are doing their best, but the problem really feels like a lack of vacuum when accelerating.

I'm more in favour of an ignition timing problem...
Check the coil is wired the correct way as they will work when wired back to front... sort of...

Coil's perfect. Nice big juicy sparks every time.

The resistance of the spark plug leads....
if they are the original VW wire type....
they should read like touching the two ends of the leads together... a dead short circuit...
This is good....

They do indeed have 0 ohm resistence. I made double sure of that. They are the wire type. Their insulation seems to be fine too.

an engine can idle with all sorts of ignition timing and fuel problems...

It doesn't like starting cold.
It can idle properly after running a couple of minutes.
It revs fine too.
It accelerates badly.
At low speeds it can pull things just fine. Ie at 0 to 10km/h.
It has a terminal velocity of ~60km/h. Independent of loading. (I had to take the car trailer I borrowed to bring it here back with the van, bacause the clutch in the falcon broke in Shepparton.)

Best of Luck

Lee Noonan

Thanks 🙂 I need it.

If at first you don't succeed. Build, build again.
Vehicle: 1975 Special order delivery walkthrough panel based LCA pop-top camper. Motor: Nippon 1.8L Single port Wasserboxer, Transmission: 3 rib 002.

General_Failure Use your head, don't abuse it!

1,036 posts · joined Jun 2004 · 13 Aug 2006, 11:25 pm

#522134

A little update.

The vac advance hose was porous. Substituting it helped a little. The idle still does its sagging trick. Ie revs can drop down as low as 100RPM before it salvages itself and goes back to normal idle.
On acceleration the revs still have the guts drop out before it picks up too. Marginally better than before. The vacuum on the tubs still feels kind of pathetic.

If at first you don't succeed. Build, build again.
Vehicle: 1975 Special order delivery walkthrough panel based LCA pop-top camper. Motor: Nippon 1.8L Single port Wasserboxer, Transmission: 3 rib 002.