Fuel pump pushrod normally tough to get in?

Chargerguy74 · July 17, 2015, 02:44:44 PM

I have a new Mancini fuel pump pushrod for my 440, and it seems overly tough to get in. I was expecting it to pretty much slip right in with finger pressure, but it seems rather stiff. Do they normally require being tapped in? I'm worried once I start tapping it's pretty much not coming out until the engine runs.

A383Wing · July 17, 2015, 03:15:48 PM

should slide in with only finger pressure.....

68Charger4me · July 17, 2015, 03:16:33 PM

It should not be tight at all, usually you have to use some grease on the top end to hold it in place while you insert the pump. Something is really wrong here if it's tight at all.

Chargerguy74 · July 17, 2015, 04:45:38 PM

Yeah, something must be off. I get a diameter of 0.4365" for my pushrod, sound normal?

A383Wing · July 17, 2015, 07:05:18 PM

I have 3 new rods here, measures 3.25" overall length, .4385" diameter in the middle

Chargerguy74 · July 17, 2015, 08:00:17 PM

Interesting. Well I went to town with some steel wool since the pushrod was a little tarnished (just cut it out of the packaging). Cleaned it up and got it to slide in with a little pressure. The bore for the pushrod looked clean, but it definitely will not drop free. A little tight for my liking. If the thing doesn't seize up when it gets hot due to friction I imagine all will be well. It'll be the first thing I think of if I stop getting fuel.

Well it's been 12 years in the making, and tonight I finally finished my 440! I started the project when I was 18, put it on the back burner for a while, stopped building and started collecting, a year ago I needed a replacement for my 340 so I pulled out the long block from storage (my dad's heated shop). I ripped out a perfectly good brand new cam, removed the new lifters, new intake, rebuilt, ported, and larger valved 516 heads, and replaced with a different cam, 440 source heads from Challenger340, new intake, EDM lifters, which required new pushrods, etc. As long as I don't wipe the cam during breakin the headaches will finally be over. Except after 12 years the paint on the block is in very rough shape. Might just leave it as is though.

Dino · July 17, 2015, 08:55:20 PM

I would pull that pushrod back out and double check things. If it's tight now it's not going to get better when it heats up. I really wouldn't take the chance that all will be well.

It took 12 years to get you here, but it may take you longer to get over not repainting it.

Do it once and do it right.

Chargerguy74 · July 17, 2015, 09:09:26 PM

Lol, yeah, it's definatly not going into a show car, but an unrestored car. I know I'd love to repaint the block if prepping was easy, something I'll have to look into. I seem to be severely challenged when it comes to making paint stick.

As for the pushrod, how tight is too tight? My pushrod sounds like it's in spec, not sure what my options would be.

Dino · July 17, 2015, 09:22:28 PM

The old paint is no match for paint remover. Or brake fluiid for that matter. Once it's off you clean it with post paint stripper cleaner, available in diy stores like Home Depot. Acetone or thinners work as well. You can also do a second cleaning with hot water and dish soap. Then dry it, mask, and paint. If the paint calls for a primer, get a 1K etch. I think the paint I've used goes onto the bare block.

Heck, scraping off loose paint and reshooting it would be an improvement but I'd spend the time to do it right. Start early and you'll be done by the end of the day. And let's be honest, what's one more day after 12 years?

The rod should not be tight at all. If you can't just slide it in with your finger then it's too tight.

Chargerguy74 · July 17, 2015, 09:28:52 PM

Well, I'll probably repaint after the break in.

This rod has me concerned now. Maybe I should try another one first. Wish I had a spare, or an old one. Welp, out it comes, be back in a bit.

ws23rt · July 17, 2015, 09:57:21 PM

Quote from: Chargerguy74 on July 17, 2015, 09:09:26 PM
Lol, yeah, it's definatly not going into a show car, but an unrestored car. I know I'd love to repaint the block if prepping was easy, something I'll have to look into. I seem to be severely challenged when it comes to making paint stick.

As for the pushrod, how tight is too tight? My pushrod sounds like it's in spec, not sure what my options would be.

About your push rod fit.--I'm going to go with Brian's measurement.--.4385"-- If your measurement is .4365" that says yours is .002" smaller than a new one.---Not a great amount to be concerned with. (I suspect your measurement may not be quite right). Check the zero ref on the mic.

If your measurement is correct you should have free movement in the bore.

As to the concern about things changing as the engine goes through heating cycles?----When the engine block heats up the bore for the pump rod gets larger as well and does so just before the rod feels the heat. The bottom line is the fit of the rod to the bore cannot become to tight because of any normal heat cycle the engine goes through.

Let's say that the bore is good and also clean. The odds of it being too small are very low. In fact so low I would say it is not too small.

If the rod does indeed measure .002" smaller than what Brian has (new rods). The only thing left that make's it feel tight in the bore is it is bent.

Chargerguy74 · July 17, 2015, 10:04:03 PM

Thanks ws23rt. I agree as long as the 2 metals have the same or similar coefficients of expansion, which I imagine the difference is negligible. Anyway, just what I feared, I can not get the pushrod to drop free. To give you an idea of how snug it is, I can't budge it with a magnet. It's starting to look like I've gotta rip the front end apart and remove the timing cover to get some pliers on this thing.

Dino · July 17, 2015, 10:08:21 PM

It's not my area of expertise by any stretch of the imagination but shouldn't the smaller object heat up and expand faster than the bigger one?

I don't suppose you could stick a smaller rod on the end of the pushrod with jb weld to yank it out?

Chargerguy74 · July 17, 2015, 10:14:27 PM

Dino, it may be possible. I wonder how well it would bond. I'd love to get in there with the mig and just tack it to a rod. Any slag would drop into the oil pan though. I think I'm gonna have to walk away from this tonight and come back fresh. I really don't want to open this thing up again.

Dino · July 17, 2015, 10:20:10 PM

I think that's a wise move.

I thought about tack welding it and you sure could with some prep, but I'd try the chemical route first...or sacrifce the rod and drill a small hole in it...but that's a bit more involved as well. Got a spray lube you can squirt in there to let soak overnight?

Chargerguy74 · July 17, 2015, 10:27:48 PM

Yeah I'd love to drill a hole in it, I'm just worried about the filings. Not sure what I'll do yet. I just know I need to stop for tonight before I do something stupid.

Dino · July 17, 2015, 10:34:00 PM

Correct! You have all day tomorrw to do something stupid! Well that's my moto anyway.

Drill with a vacuum hose next to it and regularly spin the drill the other way to eject the shavings. A magnet next to the bore may help as well.

Call it a day, have a beer.

A383Wing · July 17, 2015, 10:35:18 PM

you will never be able to drill a small hole in the rod...you don't realize how hard the metal the tip of the rod is made from...you will not have a drill bit sharp enough

Chargerguy74 · July 17, 2015, 10:37:07 PM

I was wondering that, I know it's hardened. Time for a timing cover gasket set...again lol. I don't think the cam will have that hard of a time moving the rod, but I'm not too sure about the fuel pump pushing it back up. It would be so easy for me to put the fuel pump block off plate back on right now and go electric. The pushrod can just chill in there lol.

Dino you read my mind, I was half way through a beer when I read your reply.

Dino · July 17, 2015, 10:39:17 PM

Quote from: A383Wing on July 17, 2015, 10:35:18 PM
you will never be able to drill a small hole in the rod...you don't realize how hard the metal the tip of the rod is made from...you will not have a drill bit sharp enough

I was afraid of that. Got any diamond tip drill bits laying around?

I'd still try jb or some epoxy first. I'd hate to have to open an engine to get the rod out.

I think I'm gonna grab a cold one myself now.

A383Wing · July 17, 2015, 10:40:28 PM

needle nose pliers....or the round tipped rubber hose pliers will also remove it

Chargerguy74 · July 17, 2015, 10:43:18 PM

Yeah I tried, couldn't open them up wide enough. The hole is slightly bigger up top. I'll have to remove the alternator to really get in there. I might actually give that a go soon.

Chargerguy74 · July 17, 2015, 10:48:07 PM

No dice, not enough room for needle nose pliers.

ws23rt · July 17, 2015, 10:51:33 PM

Quote from: Dino on July 17, 2015, 10:08:21 PM
It's not my area of expertise by any stretch of the imagination but shouldn't the smaller object heat up and expand faster than the bigger one?

I don't suppose you could stick a smaller rod on the end of the pushrod with jb weld to yank it out?

Hey Dino-- This just happens to be one of my areas of expertise. I appreciate your observation about the rod being smaller and therefore being of smaller mass it would tend to heat up quicker than a larger mass such as the engine block.
In this case the heat that will expand the small rod comes from the warming of the engine block. That heat comes from the combustion chambers and migrates out from there. The water jackets tend to help spread this warming out as well. The rod will only warm from the bore it is in plus a very small amount from oil (which is still warming as well).

Since the question of expansion rates has been raised and many people are aware of it this may be a good place to give an example.

For steel (cast iron is so close as to be a non issue) the rate of expansion is --about--

.000006" per degree (temp f.) times distance in in.

The tem. rise from 70deg to 190 deg. is 120 deg

the dia. of the rod is .4385"

So ---.000006" times 120 (deg) =.00072 Times dia. .4385"= .00032"

If the rod got all the heat first it would get larger in diameter by three tenth's of one thousandth of an inch. This amount is so small as to be a mute point when talking about the fit and tolerance of the rod to the block. If one were to put the rod in an oven and heat it to 250 deg. let's say it should still slide in the bore.

--Hmm this should be worth at least three cents.

Dino · July 17, 2015, 10:54:59 PM

Quote from: ws23rt on July 17, 2015, 10:51:33 PM
Quote from: Dino on July 17, 2015, 10:08:21 PM
It's not my area of expertise by any stretch of the imagination but shouldn't the smaller object heat up and expand faster than the bigger one?

I don't suppose you could stick a smaller rod on the end of the pushrod with jb weld to yank it out?

Hey Dino-- This just happens to be one of my areas of expertise. I appreciate your observation about the rod being smaller and therefore being of smaller mass it would tend to heat up quicker than a larger mass such as the engine block.
In this case the heat that will expand the small rod comes from the warming of the engine block. That heat comes from the combustion chambers and migrates out from there. The water jackets tend to help spread this warming out as well. The rod will only warm from the bore it is in plus a very small amount from oil (which is still warming as well).

Since the question of expansion rates has been raised and many people are aware of it this may be a good place to give an example.

For steel (cast iron is so close as to be a non issue) the rate of expansion is --about-- .000006" per degree (temp f.) times distance in in.

The tem. rise from 70deg to 190 deg. is 120 deg

the dia. of the rod is .4385"

So ---.000006" times 120 (deg) =.00072 Times dia. .4385"= .000032"

If the rod got all the heat first it would get larger in diameter by three tenth's of one thousandth of an inch. This amount is so small as to be a mute point when talking about the fit and tolerance of the rod to the block. If one were to put the rod in an oven and heat it to 250 deg. let's say it should still slide in the bore. --Hmm this should be worth at least three cents.

Way cool! I had no clue this was your niche!

That was a great explanation, I learned something new again.

ws23rt · July 17, 2015, 10:56:45 PM

Quote from: A383Wing on July 17, 2015, 10:35:18 PM
you will never be able to drill a small hole in the rod...you don't realize how hard the metal the tip of the rod is made from...you will not have a drill bit sharp enough

I agree

In fact I agree so much as to recommend you don't even try.

Chargerguy74 · July 17, 2015, 10:57:28 PM

Quote from: Dino on July 17, 2015, 10:34:00 PM
Way cool! I had no clue this was your niche!

I knew

I was waiting for it. You didn't disappoint, ws23rt.

Now I'm wondering if it'll operate okay. Too much at risk taking the chance I think.

Dino · July 17, 2015, 11:04:09 PM

Do you think you can get the rod moving by turning the engine by hand?

Chargerguy74 · July 17, 2015, 11:05:55 PM

Yeah, I turned it over by hand and the rod pushed out a little ways, that was my starting point. I was hoping it would be enough.

ws23rt · July 17, 2015, 11:11:42 PM

I was just going to say that.

Turn the engine over to push the rod out to it's farthest point. Then find the best way to grab the rod and be use care with easy twisting and pulling. BTW I would consider this rod as being toast so give no mind to protecting it. You should not expect to use this rod again.

---Bad rod

--

Dino · July 17, 2015, 11:17:27 PM

I doubt the rod moves enough to move it in and out a bunch of times and get anywhere. I'd still lube the rod and try though.. Damn, I think I just lured Skip to this thread.

Chargerguy74 · July 17, 2015, 11:25:06 PM

I am really thinking about an electric pump right now. 550ish hp expected and a 120gph carter mechanical? I spent all day bending up a 3/8 fuel line from pump to carb too. Well not all day, but I spent 10 hours on the engine today. Lots of little stuff. Pics when I get home.

ws23rt, this rod is dead to me.

Chargerguy74 · July 17, 2015, 11:34:29 PM

What do you guys recommend for a fuel pump pushrod? I'm gonna order a couple tomorrow if I can't find any locally.

ws23rt · July 17, 2015, 11:42:37 PM

I don't have any particular recommendation. The rod you got from wherever should have been just fine. All I can think of is that it was bent.

If it was my question I would go with what Brian (A383Wing) would recommend.

Chargerguy74 · July 17, 2015, 11:48:27 PM

The one I had was this one.

http://www.manciniracing.com/stfupupub426.html

Chargerguy74 · July 17, 2015, 11:56:20 PM

Ws23rt, do you think it would be pointless to blast co2 at the rod to help it cool and contract a bit? Would the contraction be negligible? I really don't know how cold it would get.

ws23rt · July 18, 2015, 12:37:35 AM

Quote from: Chargerguy74 on July 17, 2015, 11:56:20 PM
Ws23rt, do you think it would be pointless to blast co2 at the rod to help it cool and contract a bit? Would the contraction be negligible? I really don't know how cold it would get.

Yes the contraction would be negligible. The cooling would need to migrate up into the point of restriction and the time it would take would add cooling to the bore at the same approximate rate. It would be chasing a fast moving window of opportunity and the best contraction of the rod to be expected would be about one half of the value I talked about earlier.

If you could get a good grip in some way on the end of the rod. (vicegrips?) and add a slide hammer of sorts to the vicegrips that may ease it out. Twisting the rod in the bore as you pull.

Chargerguy74 · July 18, 2015, 12:44:58 AM

Looks like the timing cover will be coming off, one more time. Oh well. I'm thinking of trying a comp 4626A pushrod, 0.434" diameter. It's length is 3.22".

Chargerguy74 · July 18, 2015, 12:53:34 AM

It was a productive day otherwise. The fuel line does not touch the block anywhere.

birdsandbees · July 18, 2015, 01:07:10 AM

Do you not have a good pair of needle nose vise grips? I would think you could get them clamped on the end of that and then a big screw driver between the pliers and the block to pop it out. I'd be trying every trick known to man before I was dismantling the engine.

Chargerguy74 · July 18, 2015, 01:15:01 AM

I tried pliers with a much slimmer profile. There's just not enough room to open them wide enough.

birdsandbees · July 18, 2015, 01:22:01 AM

Yah.. you'd have to do some external grinding to shape them enough to get them in there. Do you have a set of brake spring pliers?? Might get them in or something similar to get a hold on it. Like I said I'd be trying everything and anything vs tearing the front off the engine.

Chargerguy74 · July 18, 2015, 01:31:47 AM

I tried a pair of really long snap ring pliers. There's nothing I can think of that has a slimmer profile. I wish I took a pic of them.

Daytona R/T SE · July 18, 2015, 08:25:05 AM

OK, This might sound stupid...

It's been a decade or more since I've had an engine opened up...

But...

If you turn the engine...

Won't the camshaft push the rod outward ?

ws23rt · July 18, 2015, 09:49:49 AM

I think the cam has already pushed the rod out as far as it can.

cdr · July 18, 2015, 10:55:41 AM

if i remember correct, you could use a long skinny screw driver through the distributor hole & push on the rod a little, maybe a welding rod.

i just looked at my old 383 & you should be able to move the rod a good amount.

A383Wing · July 18, 2015, 11:06:02 AM

I got my new pump rods from eBay years ago...NAPA, Schucks, or anyone has all the same rods....here are the pliers I suggested ...called Hose Gripper Pliers Set....

A383Wing · July 18, 2015, 11:58:57 AM

UPDATE: Went back out and re-measured all 3 of my new pump rods with different micrometers, all 3 measure .4345" in the center of the rod.

I used my 2 digital ones this time to measure....evidently I cannot add numbers correctly using the old style micrometer

sorry, my bad

Chargerguy74 · July 18, 2015, 12:34:40 PM

Quote from: cdr on July 18, 2015, 10:55:41 AM
if i remember correct, you could use a long skinny screw driver through the distributor hole & push on the rod a little, maybe a welding rod.

i just looked at my old 383 & you should be able to move the rod a good amount.

Is this possible with the cam in?

Chargerguy74 · July 18, 2015, 12:35:54 PM

Quote from: A383Wing on July 18, 2015, 11:06:02 AM
I got my new pump rods from eBay years ago...NAPA, Schucks, or anyone has all the same rods....here are the pliers I suggested ...called Hose Gripper Pliers Set....

Those look like they would work. Thanks for posting pics! Now to find some. Looks like Princess Auto has a pair of 13" double jointed ones, but that's it.

No prob on the measurements, I'm actually glad your measurements were off the first time.

Chargerguy74 · July 18, 2015, 02:55:30 PM

Picked up a new pushrod today 0.4345". Same calipers. The stuck rod is 0.4365". Not a huge difference.

Also picked up some hose pliers. They look very promising.

Chargerguy74 · July 19, 2015, 09:42:48 PM

Got it! A383Wing, thank you for following up with a pic of what the hose pliers look like. Before that pic I was sure I was tearing the engine open. The new rod fits in perfectly. I had it in and out no problem, slides out by gravity.

Dino · July 19, 2015, 09:43:58 PM

Yay!

Chargerguy74 · July 19, 2015, 09:53:29 PM

Thanks for the help! I don't know where I'd be without this forum

Dino · July 19, 2015, 09:56:02 PM

Quote from: Chargerguy74 on July 19, 2015, 09:53:29 PM
Thanks for the help! I don't know where I'd be without this forum

Happy and carefree driving a modern car! Boring as hell...

Chargerguy74 · July 19, 2015, 09:57:52 PM

Quote from: Dino on July 19, 2015, 09:56:02 PM
Quote from: Chargerguy74 on July 19, 2015, 09:53:29 PM
Thanks for the help! I don't know where I'd be without this forum

Happy and carefree driving a modern car! Boring as hell...

That sounds terrible! Lol

A383Wing · July 20, 2015, 01:04:03 AM

Quote from: Chargerguy74 on July 19, 2015, 09:42:48 PM
Got it! A383Wing, thank you for following up with a pic of what the hose pliers look like. Before that pic I was sure I was tearing the engine open. The new rod fits in perfectly. I had it in and out no problem, slides out by gravity.

Cool, glad to be of service...those pliers come in handy...

News:

Fuel pump pushrod normally tough to get in?