Help! Bombardier J5 motor makes pisscht pisscht sound

jflarin

New member
Hi,

I am very sad. I pulled a load of wood a little bit too fast and now I have a cylinder that makes a pissch sound at every revolution. It is much like if there was leaves hitting the fan, but when I start it I clearly hear that it happens with only one cylinder. It is a Chrysler flat-head motor. Anybody has experience on figuring out the problem (and then fixing it ?) I mean, should it be a (I'm throwing ideas here...) head casket? problem with valve? Piston rings? Broken block?

Thank you for all and any help,

jf
 

MNoutdoors

Tracked Evolution Central
GOLD Site Supporter
Most likely a valve, do a compression test on subject cylinder and others for reference if wanted
 

jflarin

New member
Hi,
To keep you updated, I tried to remove spark plugs. I could remove one. Two broke off. I'll try removing the other 3 later, but I fear they'll break as well. It's all rusted in place...

jf
 

m1west

Well-known member
GOLD Site Supporter
Hi,
To keep you updated, I tried to remove spark plugs. I could remove one. Two broke off. I'll try removing the other 3 later, but I fear they'll break as well. It's all rusted in place...

jf
Looks like you will be pulling the head off, if you broke the spark plugs off is likely going to include drilling them out. Look at the bright side, you most likely will see what your ticking problem is.
 

Cidertom

Chionophile
GOLD Site Supporter
Hi,
To keep you updated, I tried to remove spark plugs. I could remove one. Two broke off. I'll try removing the other 3 later, but I fear they'll break as well. It's all rusted in place...

jf
Go on and pull the head. soak the remaining plugs from both sides. At this point you have to pull it anyway. If you do get them out, see what the threads look like. If they are pitted, I would suggest putting inserts in /all/ of them. and while it's out: do all the normal head things.
 

jflarin

New member
If they are pitted, I would suggest putting inserts in /all/ of them. and while it's out: do all the normal head things.
Hi,
As far as I understand it, the flatheat spark-plugs are prone to rusting because of the cavity on the flat head and the fact it is exposed to the elements (left outside...) So I should change the spark plug more often.

It is the first time I open a motor, so I'd really appreciate if you could give me any pointers and help as to what is ``all the normal head things``. As far as I understand it, I should heat A LOT the block before removing bolts. I have a map torch for that. Beside that, what should I do?

Thank you for all and any help,
jf
 

m1west

Well-known member
GOLD Site Supporter
Hi,
As far as I understand it, the flatheat spark-plugs are prone to rusting because of the cavity on the flat head and the fact it is exposed to the elements (left outside...) So I should change the spark plug more often.

It is the first time I open a motor, so I'd really appreciate if you could give me any pointers and help as to what is ``all the normal head things``. As far as I understand it, I should heat A LOT the block before removing bolts. I have a map torch for that. Beside that, what should I do?

Thank you for all and any help,
jf
A good home made rust penetrator is a mixture of acetone and automatic transmission fluid, soak them for days then tap the metal part of the plug with a hammer and drift pin and a little heat if needed around the plug, heat the head only not the plug and they should come out. The only other option is drilling them. If you have not done something like that before, you might consider taking the head to a machine shop where there are set up to do things like that. Like CT said inspect the threads. The other thing I like to do on the old motors if you have to take them apart is install studs. More than one time I have pulled the threads on the Block re torquing the head with bolts. Also tap the head bolts with a hammer before trying to remove them. ( don't beat them just some firm taps )
 

Cidertom

Chionophile
GOLD Site Supporter
On "normal head things" obtain an old chiltons book. They may have an online version so check that as well. Doesn't matter much what, though the closer to your engine the better. Read through head checks and tests. flatness, valve seats, guide seals etc. If it's you first time pulling a head, ask around your friends circle it's always better to have help the first time. On head bolts. I agree with m1west,spend some time tapping them, light taps, don't move metal. I also agree with studs.
 

jflarin

New member
Hi guys,
Thank you for your tips did help a lot. My local 'friend' who knows those motors died a few years ago (I confirmed this week), so my daughter helped me holding the MAP torch while I removed the screw (with the tap trick). Here is what it looks like:
IMG_5130.JPG

I tried to look for Chilton book about the flatheat but I just can't find anything... Or it's about Ford flathead, or is it about 'flat rate', or it's newer years. If anybody has litterature about those motors (straight-6 flathead circa 1949 if my memory is right), I'll be interested.

I'll figure out the way to remove the spark plugs, but while I have the engine open, how can I look for the defective cylinder? (I mean, the one with compression problem/leak)? What I'm tempted to do is to plug back the battery to make it turn to inspect the motion of every valve, just to see if one stands out. If you have other suggestions, I'll be very happy to hear about it.

Thanks,
jf
 

loggah

Member
SUPER Site Supporter
Sounds to me like one of the rusty sparkplugs was allowing compression to leak by it. the valves and pistons look pretty good in the photo. I had a head with the rusty broken sparkplug problem and ended up driving out the porcelin and using a cutting torch to relieve the plugs in the head so i could get them out . i cut a slots on opposite sides of the plug and stuck a small cold chisel in the slots and turned the plugs out. Don
 

jflarin

New member
Hi Don,
It is great to read you, you give me hope!
I've been lifting all valves with the starter and none seem to have a real problem from the feeling I have on my fingertips. Of course, there is a lot of carbon deposit on the intake valve, but it does not look it is on the seating part, only closer to the stem.

This being said, I found the service manual for the 1957 Dodge and it seems that to inspect the valve and remove the carbon, I have to remove the intake and exhaust manifold... Anybody can confirm (in case I want to do that...)

I really like your idea that the heat got through the spark plug, so I'll let penetrating oil work on this overnight and try to prove you are right, homefully tomorrow.

Thanks again for all and any help!
jf
 

IMP

Member
Site Supporter
The website "Vintage Power Wagons" has parts and manuals for these old Chrysler 251 Flat head motors. And the sales people really know the engines and parts as well.
 

m1west

Well-known member
GOLD Site Supporter
Have you turned the motor over by hand while watching the valves go up and down to see if one is stuck open?
 

jflarin

New member
Have you turned the motor over by hand while watching the valves go up and down to see if one is stuck open?
Hi M1west,
No I haven't Although I could try to turn it by hand, the motor is till inside the J5, so I don't think I can turn it. However, I plug the starter on the battery momentarily (yes, this makes sparks... but I don't fear explosion since I'm not charging it) and I can check the motion of all valves. Everything seems good, as far as I can tell.

Todays update: I could remove 2 other plugs with wd-40 overnight + heat. The 3 others are broken in the head (I already had 2, I broke another one today). So I purchased penetrating oil (which will be better that WD-40) and I found the flute screw extrator my father gave me 15 years ago. I'll try to see if that can help me remove the 3 spark plug body left.

To answer your question, when I had the original problem (the pisssscht sound run running or starting the engine) it was something light (I mean, a small leak), so it wouldn't be a stuck valve. It can be a leaking valve though. Compression test will confirm, wouldn't it?

Thanks,
jf
 

PJL

Well-known member
You would need to put the head back on to do a compression test. Carefully inspect the valves and seats in the block for obvious problems. You can also try dribbling some WD-40 or something similar on the closed valves and see if it drains off quickly. From the looks of the scoring on the cylinder walls you might be looking at pulling the whole engine out and rebuilding it. It's a pretty simple engine. The best way to learn how to do it is to do it.
 

m1west

Well-known member
GOLD Site Supporter
Another thing to check is, what did the head gasket look like when you pulled the head. A blown head gasket may make that noise?
 

jflarin

New member
Hi guys,
Here is the picture of the gasket:
IMG_5133.JPG
There is a little bit of blackened section near the center 2 cylinders, but otherwise it looks nice to me. I am surprised it is all copper, but when you think about it, copper is good seal for oil drain plug plug, so it makes sense to use it here.

Should I brush off the oxidation?

In any ways, I should work on this Friday or Saturday (I have dad-duties in the week days).

Thanks,

jf
 

Cidertom

Chionophile
GOLD Site Supporter
is it solid copper or a copper fiber copper laminate? I've seen the laminate get a hole in it that caused a coolant leak. if it could leak coolant, it could leak air...
 

jflarin

New member
@Cidertom ,
It looks like solid copper to me.

Good new everyone! I could remove the 3 broken sparkplug with tips found here and in the net. I did it with 1 week of penetrating oil soaking, vintage flute screw remover and a lot of heat!

Now the plugs are removed, I reinstalled the head and did a compression test. I get 115 psi on 4 cylinders, 110 psi on the 2 others, so it looks good (note, the gauge starts at 30 psi... so maybe I should substract 30 on all readings above...)

I did torque the head (using the order shown in documentation recommended here, thanks, again for the tips) to 50 lb-ft. The official Plymouth book calls for 70 when the engine is warm, but I used aluminium based anti-seize grease. NORMALLY you have to reduce by 30 to 40 percent a dry-specified torque when you torque it wet. I could not find if the 70 lb-ft is dry torque or wet torque, so I did not take chance to overtorque. If anybody knows
 

jflarin

New member
Hi guys,
It looks like I did not click POST REPLY yesterday... So I just did to get this box to post and update.

Yesterday, after torquing the engine at 50 lbs cold-wet. I did add all new spark plugs (torqued at 20 lb-ft wet this time!) and cranked the engine. It started immediatly (the J5 likes it to be in the garage....) and have a very nice Roar. I stopped imediatly, because there is no coolant right now. I have to purchase that today.

Even if I removed carbon on the intake valve (in place) and brushed off the carbon everywhere I could (as required by the nice manuals suggested above), I am not sure if it did something significant. My guess is that the compression was lost by a spark plug, but we'll never know.

I am thinking about adding some anti-seize around the spark plug to prevent rusting. Dirty plugs are always going to be easier to remove than rusted ones... Unless somebody has another trick to prevent rusting?

Thank you again!

jf
 
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