Are you saying, "You have substituted a known good carb and it runs well?" _________________ Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100
Posted: Sun Jul 31, 2011 7:04 am Post subject: Engine Cutting Out
Hi Wes, No, we have not replaced the carb, just removed it and will send it to rebuilder tomorrow by UPS. I do have a Carter WO Carb that looks new but it seems to me that years ago, it flooded and have been reluctant to try it---but just in case we run short of things to do before we get the M38 carb back, from your post, I think you are confirming that the engine would run just fine with the WO, if it is ok???
Wes, I woke up last night thinking about the heat riser possibility; although I remember going to great detail to be sure I had it installed correctly and want to think it is fine, at 83 I know dang well that nothing is for sure. So while we have the carb off, we are going to check it to be sure.
Question: What do you mean regarding to spring systems? I worked with the manual for motors (No escapes me) and used that as a guide. I know it says to be sure to have the end of the spring on 'top' of the stop and mine is as I checked yesterday. Yet, now I want to refresh my memory as to exactly how it works. With mine cold, you can raise the arm all the way and the spring is not engaged---it does travel up some with the arm. Please explain just how heat afffects the spring and how it then raises the arm, shaft and plate.
We were really taken back with the amount of loose carbon in the carb and intake manifold. In fact we drained the oil to remove the pan so we could remove the oil pump (big, big, big unnecessary mistake and I'll hear about that from now on from my son); anyway, the oil with probably less than 50 miles on it was very, very dirty. Any clue here???
When the dust settles, I am now convinced that we have/had multiple problems, not a single one with flooding caused by a bad hand dash gas pump being one and another being too far out of time. Yet, to understand why we are where we are, you need to underestand that with the exception of the dying while hot at idle, the jeep and engine ran great.
We will be awaiting comments, hopefully, thanks again, and Semper Fi Ben _________________ Semper Fi Ben M38 & M100
It would only take a few moments to install the WO carb and run the engine. If it does run fine then you know your culprit is the profesionally overhauled carb. If it behaves the smae then you know the curlprit was not the professionally rebuilt carb.
There are two different heat riser springs used on the universal jeep line. Either spring if installed the way the other is suppose to be installed will operate the mechanism backwards.
The only sure way to know it is operating properly is to open the manifolds and heat the spring and watch which way the valve moves.
With the spring cold the valve should block hot exhaust air from the bottom of the intake manifold.
With the spring hot the valve should allow hot exhaust air to flow across the bottom of the intake manifold.
Posted: Sun Jul 31, 2011 10:07 am Post subject: Engine Cutting Out
Hi Wes, thanks so very, very much; you are a true friend and outstanding resource for all. From a glance, I am almost sure we have the top set up as shown in TM9 1804A.
Semper Fi Ben and Ben
BTW, I have heard through the grapevine that Keith B might have a good prospect for buying Leatherneck but have decided to let my son have it as he now has time to concentrate on it and really is a fast learner---you met Ben JR, if you recall. _________________ Semper Fi Ben M38 & M100
Joined: Jul 18, 2008 Posts: 639 Location: Melrose, MA and Santa Fe, NM
Posted: Sun Jul 31, 2011 10:18 am Post subject:
Whoa! That's new to me. I was fiddling with the carb this week and noticed that the flapper was loose and bounced around with the engine revvs. So, looking at the manual I saw that the spring flange wasn't seated right. But now I see there's more to it. So, when I get the carb rebuild kit and do that I can do the spring at the same time.
Does the weight "flapper" rotate to those positions on it's own, with the spring action? I guess I'm asking how I know which configuration I have.
you heat your spring and watch the coils closely if they get tighter it CONTRACTS when heated and if they get LOOSER it expands when heated. _________________ Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100
Joined: May 14, 2009 Posts: 971 Location: South Dakota
Posted: Mon Aug 01, 2011 6:47 pm Post subject:
Hi Ben, I'm reading again! It sure looks in all departments you have a fuel problem, rich at idle. Black oil and black plugs is too much fuel. The heat riser is supposed to make the intake warmer at first when fireing up the engine so the cold fuel vaporises better. When the engine is hot, it lets all the exhaust gasses flow on by and not heat the intake as much. If the spring looks like the upper WES diagram and the end of the spring comes down on top of the tab or stop, you have it right. You should have no carbon inside the float chamber where the gas is. By dirt, I mean rust brown crap from the tank. The in tank filter can get very full of that. You can soak it in laquer thinner to clean it and blow it out with air. Your carbs idle circuit is somehow letting too much gas through at a idle. You have checked the rest. Make sure when you install the returned carb from your guy, that the vent over to the cross over is not plugged with crap. We don't want crap anywhere. Ask the carb guy if anything was plugged with crap in your carb. When you fire it up again, and get a good slow idle, if the mixture screw or needle does not change the idle going in and out, you are not there yet or fixed. We want no crap here! John
Posted: Wed Aug 03, 2011 10:02 am Post subject: Engine Cutting Out
Hi John, thanks for the post. We are awaiting for the carb and an analyzer to set the rpm; we agree, we have a too much fuel problem and we think the basis for it was the hand primer pump but there may be other issues.
BTW, SINCE I MENTIONED RPM, WILL SOMEONE GIVE ME THE REFERENCE IN A MANUAL FOR THE CORRECT RPM? I looked and looked and have yet to find one. Some have said 600, others 650 and others, more.
Since Wes and Ryan intended this to be a learning and help site, and it surely is, will fess up to a couple of basic 101 errors that we have made so that any new person to the passion might learn if they are following this thread.
First, I think we fried the rpm function of my old Sears Motor Analyzer by attaching it to the entire 24 volt system rather than one 12 volt battery. We can not find any wording to warn us of that issue and since the cover of the manual clearly says 12 and 24 volt systems, we figured that since we are dealing with 24 volt, attached it that way. There is also a switch to change it from high to low rpm and I guess that is the one we were supposed to be using.
But, the 'no excuss one" was the process of changing the oil pump one cog/tooth as aligned with the camshaft so as to bring the rotor of the distributor to center of the slot for timing when we go to fine tune it. Did we attempt to refresh our memory by referring to the details in the manual---yes, we did but we read right over the most important issue. That point was in the first sentence or two that instructs to pull a spark plug and determie the top of the compression stroke. Since we had used a ratchet and socket on the nut at the end of the flywheel to get the timing mark on the pulley exactly matching the arrow on the 5 degrees BTDC, we just ignored the cycle. We removed the distributor top and maked the position the rotor was pointing, absently mindedly thinking it was pointing to No. 1 for firing. Then removed the oil pump and reinstlled it thinking we moved the gear 30 degrees and probably did---we did this through a couple of trys removng the distributor, checking, reinstalling, etc. But, when we replaced the top and started inserting the plug wires, 'viola' we now believe we had No. one on the exhaust stroke. At the moment, we think, we are not 180 degrees out but that evey thing is in sync and that if we turn the crankshaft over one more time to line up the mark and arrow, the rotor will be pointing to No 1 as it should. If all this turns out ok, we are fortunate because if we had turned the rotor to point to No. 1 with the crank in position for NO. 1 ehaust cycle, we would be in a world of hurt and not even realize why.
Wes, and others, question whether or not the fording valves are installed correctly as well as the flapper heat riser. Referring to the fording valves first. While I remember spending a lot of time being sure they are corect, that doesn't mean they are. But, looking at them from the front of the motor, both arms are pointing to the front and if you pull the handle on the dash, there is just enough rooom for the inside cable to move to close the valves for fording before they contact the round wire type cable cover. I don't see any other way they could be installed but we are open and welcome comments.
Regarding the heat riser; once again, I spent a great deal of time with the exhaust manifold on the bench and installing new shaft, flapper, and spring then testing with a torch, it appeared to open and close exactly as it should. Yet, once installed on the motor, I can not explain why when at temperature, the arm does not raise entirely to the top but can the travel can be completed manually. When cold, the arm is in the down position. As time will permit, we plan to remove the intake manifold, maybe the exhaust also, to be sure it is working as it should. Does anyone know of a less time consuming way of testing to be sure?
Enough of my wacky wisdom for today as I have already fessed up to removings the oil pan to work on the oil pump. However, we would have had to do so because the ring/expander (can't remember exact name and manual is in shop and I am here) but the removable band about 3/8" wide at the bottom of the distributor shaft came off and landing in the oil pan???
Semper Fi Ben _________________ Semper Fi Ben M38 & M100
Joined: May 14, 2009 Posts: 971 Location: South Dakota
Posted: Wed Aug 03, 2011 5:40 pm Post subject:
Ben, if the lever moves freely, and it is in the correct orientation, I'd not worry about it. It moves with the flow of the exhaust through the flapper. I think all the spring does is allow more or less flow past the flapper depending on how hot the manifold is. Stuck flapper and shaft is the main problem. The lever has a weight built in on the end to maintain some tension, but the spring doesn't totally contol it. I'd be more interested in how clean and correct your carb is. The kit I put in mine was from Midwest Military and it was the best on the market with new diaphrams which are resistant to the newer fuels. If you have a old kit, and the diaphrams are hard and brittle, they won't move and control the fuel correctly. I hope your guy knows this. John
When you finished the M38 project the drop dead at idle when warm was an issue from day one.
I believe you have had the carb gone thru at least twice since then with no change. Now it is off again for another go thru.
You have swapped coils and distributors. No change.
You have said you have checked for air leaks. Found none.
You said you have done compression checks and vacuum checks. And they check ok.
You said your fuel pump is correctly installed with the correct spacer. You said your fuel pressure is ok.
You said the fuel tank vent system checks good. Have you run the engine with the tank cap off?
You have said the carb bowl vent is clear and working.
You said the fording valves are correctly positioned. Did you disconnect them and make sure the insides were open? Some valves can have the handle installed two ways.
You have checked the operation of the PCV valve.
You assured us the correct thick insulating gasket is installed between the carb and intake.
You have assured us the valves are set correctly.
You have told us several times you are certain you assembled the heat riser correctly yet you have not positively determined the flapper is in the non-heat position. The flapper can become separated from the shaft. Contrary to previous posts the heat riser is designed to close off hot air completely when the spring is warmed up.
Carb RPM setting is listed in Par 129 on page 151 of TM 9-8012. It is 600 RPM. You'll also find the acceptable vacuum gauge readings listed in the chart above Par 128 on the same page. _________________ Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100
Posted: Thu Aug 04, 2011 10:05 am Post subject: Engine Cutting Out
Hi Wes, thanks for the consolidated list. We will reconsider each and everyone. In the meantime, here are a few comments.
1) You state: "When you finished the M38 project the drop dead at idle when warm was an issue from day one." While there may not be any difference in what I am going to write, I think it might be important to make it abundantly clear as to our assessment---apologies, if it is just a play on words: You use the word 'warm' when the adjective really is,"HOT." Drop dead idle implies to me that it dies immediately. This is not the case, i.e., when it is real hot, and I think has absorbed heat as you state in "hard to start," it begins a slow death by missing, recover for perhaps 45 seconds, miss, recover, repeating this act several times with misses getting closer together until it finally dies, unless one accelerates the motor and it recovers. As far as from day one, I'm not absolutely sure of that time frame. Heck, at 83 I don't truthfully remember what happend for sure yesterday, but to the best of my memory, that is factual.
2) No.s 2,3,4, and 5 are affirmative without any quesion.
3} No. 5 regarding compression check and vacuum check: Compression check was done just after restoration, some 5 years ago. I don't remember the figures but I was satisfied with them. The vacuum check was done at the T going into the intake manifold and met the spec stated herein. No other vacuum check was made but PSI was taken at the end of the gas line as it would have otherwise been installed at the carb and it was within specs.
4) No. 6 regarding fuel pump. I do not recall stating anything regarding the fuel pump being installed other than the result of the PSI test. I do not know what you are referring to when you say "correct spacer." I will check the manual to try and determine what a spacer there looks like. I do recall exchanging information about the spacer under the carb and mine was installed with the large spacer and metal V for atomizing.
5) I don't recall saying that the fuel tank vent system works good. I did say that we removed the cap and it did not make any difference.
6) I don't recall specifically stating that the carb bowl vent being clear and working. As a matter of fact, I forgot to mention, that when Ben JR removed the vent from the carb, there was a piece of teflon that could have restricted the air flow. I did post that the bowl was dirty with carbon particles which we related, maybe wrongly, to the flooding by the hand prime pump not working correctly.
7) I have not disconnected the fording valves this go around to see that they are open but I did take great pains to ensure that they were 5 years ago when I reinstalled them. The handles were installed the correct way.
As stated above, the correct thick gasket was installed between the carb and intake.
9) I don't recall mentioned the valves, we have not checked them but the fact that the engine runs great when cold and on the road with little chatter causes me to believe that they are or we would be experiencing missing at times other than at hot idle, wouldn't we be?
10) The heat riser: Here is where we get into an uncertain area. I know that less than 50 miles ago some 5 years ago that the heat riser was assembled correctly and tested, tested and tested with a torch while on the bench. I can not explain why now that the arm does not travel the maximum when hot although one can lift it to maximum by hand.
Here is what is confusing to me at the moment. I tested with a torch and I think this is what you also recommeded. How does one correlate the actual temperature of the torch and the temperature of the spring when the engine is at hot idle or actually when the engine reaches temp and the flapper should be completely open. Is it possble that when using the torch on the bench test that the spring was getting hotter than it would at hot idle? You stay that the flapper is supposed to open up when the spring is warmed up. Do you know the temperature reading at that point? How would one gain an accurate reading? With a therometer?
Thanks for your assurance of the incorrect timing and rpm. And, thanks for the reference for the correct rpm.
Wes, I appreciate you taking the time to consolidate these possibilities. Please take my notes above as just trying to make sure we are all on the same page. I realize a lot of it is redundant. We will be rechecking the list while awaiting the return of the carb.
When the dust settles, the amazing thing will be to me is that if the answer lies in any one of the things listed, is that most of them have been checked more than once. While I am far from being as capable now as I was 5 years ago, I was a real stictler for detail lthen and in fact not only followed the manual but received almost daily advice from you and others on g503 before you initiated this great site. Semper Fi Ben _________________ Semper Fi Ben M38 & M100
I have been following this thread all along,and have found it very informative. The knowledge and experience found here is amazing. I have a question to ask,(from personal experience) . How long and of what quality is the gas? Have you tried running it out of a gas can,thus bypassing the gas tank and lines?
Posted: Fri Aug 05, 2011 6:11 am Post subject: Engine Cutting Out
Hi DJ, thanks for you post. I had never thought of your suggestion but I think it has merit if one suspects that the tank, filter, vent or lines are giving a problem; would take a bit of work to hook up.
I might need to resort to doing so to check it out. But, what is so frusterating is that in all honesty, I took well over a year of near solid work on this project and a whole lot of expense to be sure to do everything by the book as augmented by this site and g503. In the case of the tank, mine was rusted badly in the bottom so I had it cut completely out professionally replaced retaining the original sides and top; then I had it boiled out at a radiator shop and coated with some sort of material, I forgot what, that was supposed to last for years. I installed a new filter and built new lines (not vent as I retained it); I hunted for nearly a year for the appropriate cap for my serial no. Of course, I know that many things can happen in 5 years while an old vehicle sets without running and probably has. Anyway, thanks for your interest and happy jeepen! Semper Fi Ben _________________ Semper Fi Ben M38 & M100
Posted: Mon Aug 29, 2011 3:13 pm Post subject: Engine cutting out
Hi everyone, we have been a long time getting back. We got the carb back from the rebuilder and installed it yesterday; all indications at the moment are, that was the problem. Please keep in mind that this was the third time I sent it to him---he sent us another one that he rebuilt just for us thinking there might be something with core that he hadn't found. After installagion at near 100 degrees, it started immediately and idled for some 10 minutes and didn't miss a lick until the last few minutes when a occasional miss could be detected but it did not die and didn't even sound the same. I started it today and let it idle over 15 minutes at temp without a miss. I must say the outside temp was about 10 degrees cooler today.
There may be some lesson here: The rebuilder stated that the metering rod was stuck, the gaskets were cracked, and the low idle jet orifice was plugged---enough to certainly cover all our recent problems.
Slowly, I begin to remember things and it sounds now as it did after I got it back from him the first time and the big concern then was that it after a 8 mile drive, it began to cut out at running speed but we made it home. We attributed that to dirty gasoline, maybe maybe not. The rebuilder is still a bit concerned that maybe that problem has not been solved but he is confident that he has the idle problem under control, and so do I.
So, what caused the idle problem and dying. I will offer this: It sat for 4 or 5 years and the diaphram gaskets cracked; i used Sta Bil in gasoline to keep the carb from being damaged during winter, and the only filter was the stock NOS.
Now we have a new distibutor with all new part (yes, old but NOS); we installed a hidden fuel filter, we have it closely timed with about the right rpm but will check that again as we received a replacement analyzer.
I guess we will never know for sure but we are putting our money on the carb.
I must reveal some very sad news as it explains why we have not been able to approach this problem more aggressively and that is Ben JR found out just a couple of weeks ago after months of testing that he has MDS which is pre-leukemia and started Chemo last week. With my bladder cancer problems, these two Marines have been slowed to a walk but we'll pick up the march very soon.
I can't thank you guys enough for all your help. Once we can schedule a long run, I'll post the results. Semper Fi Ben and Ben _________________ Semper Fi Ben M38 & M100
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We want no crap here! John
As stated above, the correct thick gasket was installed between the carb and intake.
Semper Fi Ben
