sam1904

So I noticed a hairline crack in the corner. I am not sure if it was the cause of the original, less severe leak that I aggravated by overtightening or if I created it trying to address the first leak. Either way when I put a dowel in the hole and wiggled it to discern if crack or shadow I found out.

Anyone got a one piece version of this that is for sale?!

To answer the question "is that how the engine was assembled - I don't know. The RTV is but the pinched gasket may have been me tightening the bolts too much when I was trying to stop the leak.

Culprit?

I cleaned all the RTV off and used a stone. Should I use RTV when reinstalling? (hate the stuff!)

22 hours ago, John76 said:

You did put that special washer on the OUTSIDE of the dizzy flange ... didn't you?

Sounds like a lot of oil coming out between the head and the housing.

Head, paper gasket, flange, sealing washer, M6 short bolt.

Sorry....just checking.

 I did indeed, I am still amazed at how much oil forced out between the casting / washer / bolt head! Looking at the floor I would guess 1/4 quart in 30 seconds. The guy who built the motor claimed high oil pressure - I guess he wasn't kidding!

p.s. I just bought this motor after zero miles on a build and it looks like the gasket is new (as are all others)

Hi All,

I finally used the oil dye, and IR goggle / lamp today to try and track down my oil leak(s) on this new motor. One of the areas I saw history of a (small) path of oil from was around the 'self sealing washer' below. Being the hack that I am I took it out, wiped it off and reinstalled (TIGHT). I then started the car and had a TORRENT of oil from this area...... I put a flashlight on it for 10 seconds and it seemed to be coming out around this bolt, between the head and housing specifically

I again removed the bolt and washer fearing the worst but see no cracks etc. in the housing photo I took below.

So now I am confused. When I look at some images I found below it appears that this hole is fully surrounded by gasket and hence should not see oil, I also stuck a toothpick in it and confirmed it is a blind hole so again no oil on the bolt... Given this why does this bolt need a special sealing washer and how can the volume of oil (e.g. a quarter to a half a quart in 20-30 seconds after I reinstalled and tightened!) I saw coming from around it be resultant?

Am I missing something?

Thanks

Sam

57 minutes ago, tzei said:

Flat washer & plain nut

Thanks, just saw this after doing plain nut and thin wave washer. 
Hopefully all good!

 Sam

Thanks all,

Just installed the new drivers (LHS) side and noticed with the washer and deep flanged nylock that was in place there is not a lot of thread engagement on the outside bolt and definitely not any contact with the nylock element.

What nut should be used here (parts diagram don't see to give any dimensions).

• Should there be a washer against the slotted subframe mount element - if so flat or spring?
• Should it be a plain, flanged or nylock nut?

Thanks
Sam

Going to secure / lift under the sump (carefully) with a Jack and wooden  block.
 

Just to be sure I understand - are you saying it is, or is not possible to move the motor enough to remove the rubber mount without removing the engine block mounted bracket? It is the bolts securing that bracket to the engine block that I am not able to break in the space I have.

 Thanks

 Sam

Hi, struggling with the driver side motor amount as I am struggling to get any meaningful torque on the bolts (red) that hold the bracket to the block (I am also worried that even if I do get them off I will then not be able to get enough torque back on them to be confident in that bracket not moving).
Do these definitely need to come off or if I just release the nuts (yellow) on the mount itself has anybody had any luck rocking the motor over enough to allow the threaded rods to escape the brackets?

11 hours ago, Dudeland said:

eh hem... does anybody what a set of poly motor mounts LOL.   I got them just in case the turbo started to flex things too much.  In the back of my mind I always knew that they were super harsh. 

 

Ahem, TWO pairs! ?

Thanks all, I had previously been advised to go with poly mount but this post now has me going back to stock!

(yes, I did reinforce the subframe!)

All,

I have a 76’ 2002 that I did a 40DCOE install on around a year ago and installed an A/F gauge. The car has been running really well and other than a very minor ‘transition’ stutter sounds and runs fantastically all the way to red line. OK, it soundED, and rAN well until recently….

• The car was parked for around three weeks recently and prior to that was running great, A/F ratio from low 13/1 climbing to 15/1 ish at higher RPM
• After storage (or whatever happened) the situation has had a step change.
• The car now runs far leaner and although the change is not as significant at idle it now leans out to 17-18-19/1 at higher RPM’s (E.g. 4000) and especially in 3^rd / 4^th gear and associated speeds.
• As expected with this A/F ration the car stumbles badly above 3-4000, especially under load.
• Initially I had wondered if the change from 70F temps previously to 30F the first few times I had the issue created the problem given denser intake air. Subsequently I have had the chance to drive the car back in the 60/70F range and the issue persists
• I pulled the plugs and while they all look lean no single plug, or pair seem to be worse
• I pulled the jets and blew them out with no luck.

Before I dig further, and blindly does anyone have any suggestions?

Thanks as always,

Sam

53 minutes ago, Hans said:

You do have plastic floats, right?

Indeed I do! New 151 carbs. 

Also - no fuel pressure regulator but I am using the low pressure pump (2-4psi) from IE...

Thank you for all the comments which I need to read and digest. Between waiting on some different tubes to arrive and then spending three days searching for gas so I could drive the damn thing it's been a while since I gave an update so while I digest the content here is a quick update on the last few days.

I changed to F16 tubes as suggested by a couple and worked on fuel level. I am still struggling (or over thinking it) as measured with the tip of my calipers I am now sitting at around 28mm fuel level but this required going to 10mm (not 12mm) float clearance at center. To get in the 27 range will move me to 8-9mm which I will try later.

With the new F16 tubes, jetting as shown at start of thread and idle screws out 2 turns my A/F at idle is close to / slightly above 11:1. I still have the stumble but it is slightly better and can now be (mostly) driven around. I also have Chris Joyner here in town and as I have a couple of other things I have worked on I would like him to cast an experienced eye over I will see what his highly calibrated ear makes of this next Thursday!

Will review the thread above and get to 27mm and update further.

Thanks

Sam

Thanks all, I’ve checked my float level and driven several times. I have plastic floats and each time I think I am bang on setting it at 12 mm at the center of the float. When I then measure fuel level with the carbs assembled it is around 29 mm and not 27 mm. I am assuming I should dial-in on the fuel level number even if it results in slightly less float gap?

Quick question. After pulling the main jet and filling the bowl at idle can I shut off to measure or does it need to be running?

Thanks

1 hour ago, Chris_B said:

Have you checked your fuel levels?

I will read up how to do this with these carbs. Any set level you would propose or just whatever is 'standard' in the book?

Thanks
Sam

Thanks All,

One thing I should have shared is why I installed the carbs 5 months ago and am only seeking help now. There had always been a slight 'stutter' at this point but I just drove around it. It has now got (far) worse and is a definite 'stumble' that is hard to drive around. So, the key question is what changed......?

1. Weather got warmer.. (Can't see this as an issue as lower air density should have helped, not hurt this)
2. I changed from IE 90 Elbows and individual POD filters to Koogleworks cast 90Deg inlets and a single foam filter (See image below). This does not seem to have changed inlet length at all / much but I  assume this increased inlet flow as it appears to be a lower restriction (higher quality...) set up?

I will research and check fuel levels tomorrow and if that fails change emulsion tubes as suggested. Thanks again all,

Sam

OK, after some driving and wrenching to complete my homework assignments here is what I have:

Observations driving the car:

• The lean condition appears to only occur between 2000-4000 RPM (mostly 2000 – 3500). It does not occur during that RPM range every single time (or at least to the same extent) but is more often than not present.
• When accelerating (especially in 2^nd and 3^rd) it tends to be 2000-3000 RPM and as I apply throttle I move through it quickly
• Depending on load it can occur as a quick spike anywhere in that RPM range, or with slow throttle application in a high gear be present through much of that range
• It DOES seem to be clearly correlated to a specific throttle position and always seems to occur at around 20% throttle travel.
• If I pass through this throttle position it is a spike, if I hold the throttle there, or decelerate under a trailing throttle to that point the lean condition can be sustained for seconds at a time
• The lean condition does not seem to occur at any other throttle position under any RPM or load scenarios

Wrenching observations

• The car has 45 (4.5mm??) Aux Venturis. (See pic below)
• I have previously balanced the carbs, both between and within using both my squirrel cage and carbtune
  • I had to open the air bypass jet slightly on #4 to achieve this 
• Idle speed is around 900-1200.

Does this help?

Thanks

Sam

Thanks for all of these thoughts, lots of strings for me to pull.
 

When I get back to the car later I will take some photos, check out what I have in the auxiliary venturis and also take it out for a drive to check not just the RPMs but if it is purely transition issue or if it is also at steady state at those RPMs.

Will report back later!

I am curious though. It is not that when I transition to the mains it leans out and then gradually enriches as throttle progresses, it seems to be just a short spike at a specific position and then it ‘switches’ back to 13-12.5:1 and stays there... ?

Will pull the filter and elbows tomorrow and check...