1986 holiday rambler cranks but won't start

[dakattack]

greetings all,
New member here so please be gentle! I own a 1986 Holiday Rambler that we took out several times last year, the rig did start after alotta pumping on the accelerator. This year, I took it down to fuel up, fired up, idled fine, then when I went to start it after, it cranked but would not fire. I did check for spark and it has that, now, I need to ask, where do I go from here? as I said earlier, very new to RVs as well as this site.! any assistance is greatly appreciated.!!

[stanDman111]

sounds like a fuel delivery problem

[Rickf1985]

Ok, I have heard of HR's on Chevrolet chassis and Dodge chassis and now a Ford chassis, all in the same age group. They certainly spread their allegiance around didn't they?
Yep, sounds like a fuel delivery issue. The easiest way to tell is to take the top off of the air cleaner and look down the carb throat, you will have to hold the choke plate open by hand and pump the gas. You should be getting strong streams of gas from the pump squirters in the middle of the carb. No squirts means no gas usually. The usual culprit is a bad fuel pump BUT, when was the last time you changed the fuel filter? It is cheaper and easier to change a filter than a pump. Take the old filter and shake it towards the inlet over a rag or small pan and see if a bunch of dirty gas comes out. If it does then that was at least part of the problem. If the fuel pump has never been changed then figure it is 29 years old and probably weak at best. I don't know if Ford uses an electric pump in the tank like GM.

I am thinking the engine you have is probably a 460 and not a 360.

[DaveVA78Chieftain]

Hmm, Ford stopped making the 360 in 1976 https://en.wikipedia.org/wiki/Ford_FE_engine

If this is a Class A rig, Is it possible this is a John Deere chassis with a 460?

If Class C, then 351 or 460

[DRMousseau]

I'm sure we'll get more specifics on this. I'm thinkin 460 also as the I believe the HR Imperial is a pretty big Rig.


My '87 Cruise Air II also has a 460 Ford,.. I'm on a John Deere Chassis. Like Rick noted, you SHOULD get some good squirts when looking down the carb throats while activating the linkage. But little or no squirts may also be a carb problem,.... mine was pretty gummy and I was surprised I even got it home when I bought it. The accelerator pump was also in bad shape and was squirtin' very poorly sometimes not at all. And I dreaded the thought of a fuel pump replacement,... but that's what it initially looked like.


Loosening the fuel lines from the carb (or pressure regulator) quickly relieved my anxiety somewhat, as fuel flowed freely from the lines. If it hadn't,... I'd have gone further toward the fuel tank loosening lines. Rick also noted the fuel filter, usually the next stop to check for flow. If you get to the last connection with nothing more to the top of the fuel tank, and still have no flow,.... then you might think seriously of that fuel pump. SOME of these carbs also had a screen that was easily removed to be cleaned or replaced jus inside the fuel inlet. Mine didn't,... but I had fuel there and that meant my carb jus wasn't gettin' that fuel into the engine. While it ran IF it started, it was jus kinda runnin' poorly.


In my case,.... it was a failed accelerator pump AND a really gooky carb. A simple clean and rebuild, and what a difference!!! Still only get 6mpg,... but hey, it's a big block 460!!!


All that pumpin' on the accelerator to get it started??? Kinda tips me to thinkin you have similar issues as I. Ya see, with a Chevy ya pump the daylight's outa 'em and keep pumpin' when it finally fires up. But with a Ford,.... pump it more than once, and your flooded!!!! Then ya gotta wait a good time, to dry it out and try hard not to flood it any more than it is!!! If your pumpin' it to finally get it started,... then your accelerator pump is torn and bad. When you rebuild your carb and/or replace that accelerator pump,.... you will see that difference BIGTIME.

[dakattack]

sorry guys, fat finger syndrome,, it is a 460. anyway, thanks for the leads, when it warms up a bit, I now have a starting point.!

[DRMousseau]

Fat fingers? I would've blamed spell check.  W%


You know those folks that saved hundreds by switching or something? Well, IF you find you DO need a rebuild carburetor,.... don't be afraid to tackle the job of rebuilding yourself rather than switching carbs. I saved a few hundred myself as the Motorcraft/Holley rebuild is VERY easy to do. Think I spent about $50 or so in rebuild kit and 10hrs TOTAL in removal, rebuild, reinstall, and fired it up (I'm an old man and it takes me more coffee breaks, snacks, and extra bathroom time than many others need for the job). But much less expense than the hundreds that a rebuilt carb costs today!!!!

[Rickf1985]

Be sure to check for fuel flow at the line before tearing into the carburetor. pull the line off the carb and put it in a can and turn the key on, see if anything comes out. If nothing then you do not have an electric pump, at least not one that is working. Try cranking the engine and see if you get good strong spurts of gas, no spurts or weak spurts means bad fuel pump. I am not thinking gummed carburetor if it was running good not long ago. By not long ago I mean last season. Not saying it can't happen but always check the easy things to check first.

[DaveVA78Chieftain]

Now that we know it is a 460, update your signature to say 460. 
Now, find you chassis VIN plate and see if it a Ford or a John Deere chassis.  Both used a Ford 460.
Either way, this would basically be the first year for either one.
Gotta know this stuff for repair parts.

[DRMousseau]

Yup,... what he said. Next most important is the chassis the engines in!
IF,... and I somewhat suspect,.... this IS a big John Deere chassis with that 460 Ford, then it does have some uniqueness. But I don't recall much of Fords Chassis to know how different the fuel systems might be.


But checking fuel flow AT the carb inlet, can be deceiving! That's because the inlet line to these big carbs, comes from a nearby fuel pressure regulator. It's a VERY low pressure regulator, so you may NOT see the strong flow or spurts as one would normally expected. This caught me a bit by surprise, and worried me a lot. Best to check flow on the INLET side of this regulator, where you can expect that typical unrestricted flow. Depending on the overall system, you'll want to check for this flow in a couple of manners,... with ignition on and/or while cranking engine. If it's weak or non-existent then you might suspect the fuel filter (next down the line), by removing carefully (you'll want to keep the fuel in the filter to examine for condition), and repeating the test of ignition on and/or cranking of engine. IF there is still no fuel present at the filter inlet line,.... then ya gotta suspect the fuel pump and/or the electrical system of the fuel pump.


Yup,... it's probably an electric fuel pump. IN MOST CASES (not always),... if a fuel tank isn't in close proximity of the engine (such as saddle tanks, a side tank, or forward mounted tank), then it will have an electric fuel pump either in the tank or on the frame near the tank. This is because engine mounted mechanical fuel pumps SUCK!!!! Seriously! And they're not as efficient sucking fuel with vacuum over a long run, as a pump that pushes fuel with pressure over a long run. Even efficient electric pumps will be in or near the tank for that benefit, because they don't suck so good either. AND, the nature of the Holley/Motorcraft carburetor requires low pressure (high volume) fuel flow to prevent damage to the accelerator pump diaphragm which is unique to these carbs and quite unlike the piston type accelerator pumps of many other carburetors. This diaphragm can become porous, cracked or torn easily, and why you may be having to pump the accelerator hard to start it up in the recent past. Seems I recall some small unnoticed fuel leakage in this area when running. Unnoticed because it may not accumulate much before engine heat evaporates it away, and of course it's not leaking much when not running. But a porous diaphragm will cause the float-bowl to empty, and also cause long cranking and hard starting. So check for a small leak after cranking in this rather easy to access area of the carb.   


I believe I have an in-tank fuel pump, but depending on year and chassis model, John Deere did have some frame mounted fuel pumps. Not sure about Ford chassis, again, the fuel tank location is often a giveaway in whether it has a mechanical or electric fuel pump. Surprisingly, the in-tank pumps on John Deere's seemed to last longer than the others and often outlasted the wiring, connections, fuel lines, and other components too. Good thing too,..... cause it's NOT easy to replace. N:(

[DaveVA78Chieftain]

The Ford F53 Motorhome chassis did not start until 1988 and they were all Fuel Injected.

Carburated 460 versions (Holley 4180-C) of the John Deere chassis have a 4.3psi, 25 gal/hr electric fuel pump that is externally  mounted to the front side of the fuel tank.  No seperate regulator is installed like is used on a GM P30 chassis.
According to the JD Manual, There are 3 fuel filters. 
One in the external fuel pump at the tank (refer to manual for information)
One in-line on the left side frame rail
One bronze filter at the carb inlet.

Fuel Injected JD chassis used an in tank fuel pump.
Has a sock filter on the fuel pump pickup
Has a in-line filter on the frame rail

All this type of nformation is in the manuals so I suggest you determine what chassis you actually have before you go on a wild goose chase.

[DRMousseau]

DANG! Cant believe I don't have this manual for John Deere,... but a check of my purchases says I didn't either. SO,... I better get one while the gettin's good!


But I do have a parts pdf and a link to same chassis parts pdf,... http://jdpc.deere.com/jdpc/pdfs/PC2109.pdf
Hope that works. Limited info of course,... jus a general chassis parts list.
Page 20-1 show the pressure regulator I have,.... and ya made me get out in the rain and crawl under with a flashlight. In-tank pump! UGH! Good thing my "bubble" keeps the rain out, nice and dry under there. Page 30-10 shows the fuel tank system I have,.... with 90gal and internal pump options.


And the in-line fuel filter was in the standard spot, I'll assume a sock on the in-tank pump, and since "I" rebuilt the carb, I omitted the "bronze stone" at the fuel inlet, not sure if I added an additional metal/glass in-line or not. It's still winter sorta, and my cab area is cluttered and closed off for heating purposes, so I didn't dig to the dog-house and look under.


The PO stated that it runs ok when I bought it, but is in need of a tune-up. He too was pumpin' on the throttle and cranked it near dead before started. Not normal for a Ford. I noticed as I drove it home that the throttle was rather unresponsive and was starved if I tromped it,.. again not normal. When I got home and peeked into the carb throat, I could see the accelerator pump was barely squirtin' in there. Familiar with these, I put a folded paper-towel under the accelerator pump arm, and started it again. Within a few moments, the telltale wetness showed on the toweling,... yup, porous diaphragm! I could get a pump diaphragm and necessary gaskets separate, still required carb removal to repair. So I considered a rebuild kit that included everything and would look inside a few areas to inspect it, clean, and do whatever necessary. Float and bowl chamber look ok, jus a little cleaning, primary too not bad. BUT THE SECONDARY METERING BLOCK,.... UGH!!!! Inside that area was a slimy, gummy goo in every corner!!!! Couldn't believe it ran at all, but it did! And was surprised when I saw the condition of this!!! Talk about snotty nose!!! YUCK!!!! So,... full disassembly and cleaning, heck, I had the kit and all I needed plus extras for the models I didn't have. lol.


I questioned fuel flow at the inlet line, seemed weak but was fine on the inlet of the regulator. Replaced chassis mounted inline filter and it need it. Hooked it all back up,... and it's been WONDERFUL!!! Did a typical tune-up and maintenance but it really wasn't necessary, except lube and oil change. All replaced parts were in great shape including plugs,... now they are all backups, jus in case. 4000+mi later,.... still great! Fired up once a month thru the winter here in my "bubble", jus like it started and ran yesterday,... WONDERFULLY!


Still need that manual though,.... can never have enough references!

[DaveVA78Chieftain]

John Deere Service Manual

Covers everything except the 460 engine itself

[Oz]

changed profile to reflect 460.

[dakattack]

this is a great site.! thanks for all the tips guys. ill be checking back here time to time and let you good folks know how it goes. Gta get it going soon!

[dakattack]

changed profile to reflect 460.

thanks for the assistance friend~!

[dakattack]

update: pulled the hose at the carb, absolutely no fuel flow at all, and no sound of the pump kicking on, I did replace the inline fuel filter last season but checked it anyway, it appears to be good as it is clear and has fuel in the bowl,, so I guess a new fuel pump is my next step?

[dakattack]

I'm sure we'll get more specifics on this. I'm thinkin 460 also as the I believe the HR Imperial is a pretty big Rig.


My '87 Cruise Air II also has a 460 Ford,.. I'm on a John Deere Chassis. Like Rick noted, you SHOULD get some good squirts when looking down the carb throats while activating the linkage. But little or no squirts may also be a carb problem,.... mine was pretty gummy and I was surprised I even got it home when I bought it. The accelerator pump was also in bad shape and was squirtin' very poorly sometimes not at all. And I dreaded the thought of a fuel pump replacement,... but that's what it initially looked like.


Loosening the fuel lines from the carb (or pressure regulator) quickly relieved my anxiety somewhat, as fuel flowed freely from the lines. If it hadn't,... I'd have gone further toward the fuel tank loosening lines. Rick also noted the fuel filter, usually the next stop to check for flow. If you get to the last connection with nothing more to the top of the fuel tank, and still have no flow,.... then you might think seriously of that fuel pump. SOME of these carbs also had a screen that was easily removed to be cleaned or replaced jus inside the fuel inlet. Mine didn't,... but I had fuel there and that meant my carb jus wasn't gettin' that fuel into the engine. While it ran IF it started, it was jus kinda runnin' poorly.


In my case,.... it was a failed accelerator pump AND a really gooky carb. A simple clean and rebuild, and what a difference!!! Still only get 6mpg,... but hey, it's a big block 460!!!


All that pumpin' on the accelerator to get it started??? Kinda tips me to thinkin you have similar issues as I. Ya see, with a Chevy ya pump the daylight's outa 'em and keep pumpin' when it finally fires up. But with a Ford,.... pump it more than once, and your flooded!!!! Then ya gotta wait a good time, to dry it out and try hard not to flood it any more than it is!!! If your pumpin' it to finally get it started,... then your accelerator pump is torn and bad. When you rebuild your carb and/or replace that accelerator pump,.... you will see that difference BIGTIME.

greeting Dr, where would I find that accelerator pump? Is it up by the carb by chance? Thanks!

[Rickf1985]

No fuel to the carb don't even worry about the accelerator pump, it is not your problem. It is inside the carburetor.

[dakattack]

thanks Rick, Id already decided to rebuild the carb, but not hearing the pump kick on has me a bit worried as well. any thoughts?

[DRMousseau]

You'll find the accelerator pump jus under the float bowl beneath the fuel inlet end.


Clear filter show fuel,.... but did you try for fuel flow at the filter and had it disconnected??? BOTH with ign on and while cranking??? Some systems had an added switch in the circuit that was only activated after cranking a few moments,.... usually an oil pressure sensor. That meant it sometimes took a few moments of cranking to start fuel flow. Not an issue with fuel in the carb and the accelerator pump loaded. It normally would start right up with a single pump or two, and the delay wasn't even noticed. But if you've pumped it dry, or it drained empty thru the diaphragm,... it would take A LOT of cranking till float bowl was filled and accelerator pump primed enough to give ya a starting squirt! This makes for noticeable hard starts when cold, and fruitless pumping,.... easy restarts even after several long minutes, unless it has sat long enough to drain that float bowl. Then it's a long crank again, because it drained slowly thru that diaphragm and of course evaporated on the warm engine,... no sign of leaks. The float bowl doesn't hold a great deal to leak out.


And don't be so quick on that fuel pump,... MAKE SURE, it's really not working!!!! MAKE SURE it's getting power back there!!! I hate that pump job so much I'd even "hot wire" it straight up hoping to FORCE it to work! Only then, if directly powered, and it still didn't work,.... then I'd concede to a new pump replacement. Still could be broken wires at the top of the tank, but if ya got it down and discovered that, I'd probably still replace it, jus so I'd never have to worry of it again.


But I'd be checkin' EVERYTHING else first!!! Fuses, connection ends, ground connections, relays, and every inch of wiring where it hangs or touches anything!!! Weather changes at this time of year can contribute greatly to total failure where last fall it was marginal and unnoticed. High humidity and abrupt changes in temps can cause ground issues and even terminal connection issues. Often voltage is present, but insufficient current flow due to corrosion, rust and looseness, prevents proper operation. Look for "green" wires at terminal ends, and cut back to good wire and crimp with new terminal ends.


Imagine emptying to a manageable weight (?) and dropping that tank, replacing that pump with brand new,.... and finding it STILL doesn't work!!!NOW, you still have the task of troubleshooting your wiring and power supply! And jus because I have voltage back there,... doesn't mean I have good power and current flow. It's helps to have some assistance, then one could see a possible voltage drop that may show a connection problem. But if I'm alone,... THAT'S when I connect a direct power source OR another load to that end. If I couldn't get, say my back-up water pump or a spare sealed beam to work on the end of that line,... then I know my wiring is bad. If my fuel pump works with a direct hook up to my spare battery,... then I KNOW my pump is good and I better trace wires and connections closely!

[Rickf1985]

First find the pump relay and make sure it is passing power to the pump. It is much, much easier to replace a relay than the pump. I cannot help you with the location of it since I am not familiar with your coach. If you do find that power is going back to the pump and you have verified by someone back by the tank the pump is not running then you are in for the treat of dropping the tank. We put up a discussion in the Chevy section I think it was about a safe and easier way to do that using threaded rod if you get that far. Are you sure this is a carbureted engine and not fuel injected?

[Rickf1985]

I just checked a PM I had gotten a while ago and if this is a John Deere chassis then you may have an external pump mounted near the front of the tank. This would be a good thing for several reasons, first is the obvious reason that you don't have to drop the tank to get to it and second you can check the wiring right at the pump to es if it is getting power. If it is getting power then be sure the ground wire is clean, it is probably connected to the frame nearby.

[DRMousseau]

Yes Rick!!! And it would be SO nice if my John Deere Chassis had an external fuel pump. I so dreaded possible problems when I experienced similar symptoms of fuel flow and unable to hear the pump runnin'.


But an external pump would ALSO have possible connection problems that many experience this time of year, being exposed on the frame below the vehicle.


John Deere made the basic chassis with Fords setup,... depending on chassis model they were all about the same, with later ones being injected engines. But RV manufactures had their own steering columns, and a few other variations and setups specific to THEIR make and model. It might be unfair for me to assume that's it's the same chassis as I have, but given a it's a year older than mine, and about the same length,.... I think I'd be guessin' close. But of course there were variations even on the long heavy chassis. It appears the big 90gal fuel tank had BOTH internal and external options of fuel pumps, the small tanks had only the external pumps.


And like Rick said,... check that relay too! I've had 'em suddenly fail, and inside found it was jus a big ROCK of corrosion. Still worked, till the change in weather caused too much dampness in the corrosion.

[dakattack]

morning guys, since I filled both tanks just before this problem, you can bet I'll be checking all those things! dropping a full tank is NOT something I look forward to. The relay, I hadn't even considered that, thanks again guys. Stay tuned, I'm going in!! lol!