474CJ freeze-up - culprit

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474CJ freeze-up - culprit

Post  gcj on May 6th 2018, 6:52 am

Well, those of you who suggested the thing that broke my 474 was a plunger retainer clip, were right on the money.



Here it is:



When I first started this engine I remember I had a tough time getting the valves adjusted, due to its very high oil pressure, and somewhat lopey idle. It took a while to get it set. After that no problems. The engine had circa 1500 miles on it when it froze up. The heads were milled. CR was around 12:1 and thus I had overheating problems, especially when I ran it on low grade fuel. (high octane is not always available).

Does anyone know what may be a likely cause?


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Re: 474CJ freeze-up - culprit

Post  DaveMcLain on May 6th 2018, 9:25 am

gcj wrote:Well, those of you who suggested the thing that broke my 474 was a plunger retainer clip, were right on the money.



Here it is:



When I first started this engine I remember I had a tough time getting the valves adjusted, due to its very high oil pressure, and somewhat lopey idle. It took a while to get it set. After that no problems. The engine had circa 1500 miles on it when it froze up. The heads were milled. CR was around 12:1 and thus I had overheating problems, especially when I ran it on low grade fuel. (high octane is not always available).

Does anyone know what may be a likely cause?


It probably came out when the engine was over revved one time or another and broke the end off of the wire which caused it to come out of the lifter.

High compression isn't what's making it run hot but having to crutch the engine to get by on lower quality fuel can cause over heating. When you have it apart to rebuild that's also a good time to drop the compression down and make the engine work on the fuel that's available.

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Re: 474CJ freeze-up - culprit

Post  427John on May 6th 2018, 10:14 am

If these are hydraulic lifters the very high oil pressure you mentioned may have also been a contributing factor.Installing screens in the oil drainbacks will prevent this particular failure from happening.

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Re: 474CJ freeze-up - culprit

Post  pmrphil on May 6th 2018, 11:02 am

As Dave said, overrevving and or improper valve spring pressure are the likely candidates, also incorrectly adjusted rockers won't help. Too high of an RPM (even just once) stands out as the most prominent cause.

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Re: 474CJ freeze-up - culprit

Post  rmcomprandy on May 6th 2018, 11:44 am

95% of the time, that wire clip is deformed and pushed out by the plunger being at the very top of its travel.
 
When the inner plunger is down at least .020" it almost never will come loose. That is why short travel hydraulic lifters meant to run near "0" lash have a more positive retaining clip.

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Re: 474CJ freeze-up - culprit

Post  BOSS 429 on May 7th 2018, 12:11 am

gcj wrote:Well, those of you who suggested the thing that broke my 474 was a plunger retainer clip, were right on the money.



Here it is:



When I first started this engine I remember I had a tough time getting the valves adjusted, due to its very high oil pressure, and somewhat lopey idle. It took a while to get it set. After that no problems. The engine had circa 1500 miles on it when it froze up. The heads were milled. CR was around 12:1 and thus I had overheating problems, especially when I ran it on low grade fuel. (high octane is not always available).

Does anyone know what may be a likely cause?






not setting the lash right ( preload) by not having the lifters pumped up correctly when setting valves can cause the plunger to top out,and push out the clip when engine is running,is the pushrod bent,or beat up?
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rods

Post  gcj on May 7th 2018, 2:25 am

Pushrod(s) are fine, no damage.

In view of this it seems a foregone conclusion that when I rebuild this engine, solid lifter seems to be the way to go. I can´t stand the thought of a 2 cent clip destroying a high dollar engine. Whatever the reason for its popping out of its proper seat.

The whole valve train setup consists of matching parts from Crane. That includes valve springs. 99893 - 16 to go with the 354551 cam.

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Re: 474CJ freeze-up - culprit

Post  427John on May 7th 2018, 10:21 am

gcj wrote:Pushrod(s) are fine, no damage.

In view of this it seems a foregone conclusion that when I rebuild this engine, solid lifter seems to be the way to go. I can´t stand the thought of a 2 cent clip destroying a high dollar engine. Whatever the reason for its popping out of its proper seat.

The whole valve train setup consists of matching parts from Crane. That includes valve springs. 99893 - 16 to go with the 354551 cam.
gcj the answer here is not to build the valvetrain to withstand stratospheric rpm's especially if you intend to keep the stock rods that will just shift your catastrophic failure to somewhere else in the engine with even more catastrophic results.The answer is evaluate the rpm capabilities of the engine based on the parts used and the assembly and limit your rpm's to that.People exceed the safe rpm of an engine at times and sometimes they get lucky and get away with it,just as often they don't.

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RPM treshold

Post  gcj on May 7th 2018, 3:17 pm

This motor never once went past five grand.

The rods are vintage CJ jobs with ARP bolts.

What would be a decent rod / piston setup for this engine, using the 460 crank and staying with the ,060 OS bore? (4,42")

Any suggestions on stroker kits from members on this forum? (Vendors)

G.

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Re: 474CJ freeze-up - culprit

Post  427John on May 7th 2018, 7:08 pm

G,if your goal is for a hot street car that won't see north of 5800 rpm the combination you have should be sufficient.I haven't looked up the specs of the cam you listed so I don't know if it would be optimum,also the small chamber CJ heads and early short deck (10.300) block will hinder getting to a pump gas friendly compression ratio.If your cyclone is an original CJ car I can see wanting to use them,but the sad fact is that a set of Mad porter spec D3's will make a much better set of heads for the street.A set of those on your existing shortblock freshened up would allow a tune that would make a nice strong street engine.A stroker setup that would require more extensively ported iron heads or aluminum heads isn't required to be able to destroy most street tires a 472 inch engine should be more than capable of that.The photos you posted don't show any damage that a rehone crank polish or grind and a new set of rings and bearings won't fix.
P.S. You can always grind off the D3VE-A2A casting number if you want to keep people guessing.

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D3´s

Post  gcj on May 7th 2018, 7:16 pm

I have two sets of bare D3VE heads. One of these sets has intake ports matched to CJ size intake manifold ports.

I also have an original CJ spread bore intake w. a 7040288 Q-Jet as well as a Weiand 8021 CJ size ....

Thanks for taking the time out to make these comments. They really do help. I need to take this thing apart down to its gene strands ... mainly to find the rest of that plunger retaining clip.

Using the D3VE would include installing 2.19 / 1,76" valves, right?

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Re: 474CJ freeze-up - culprit

Post  427John on May 8th 2018, 5:59 pm

Depending on the level of desired performance, possibly, the mad porter has different stages of improvement for those heads that use incremental increases in valve size so you can tailor your heads to optimize the rest of your combination.Keep in mind that if you prefer to use the CJ quadrajet intake you don't necessarily have to open the intake ports to match it may only require minimal blending to be optimum.The porter would be able to advise you on that,he would need the specifics of your drivetrain and car weight to map out your path forward.He will be able set you up with a distributor curve and a custom spec. cam to match your combo if necessary.An engine build using your existing components would want to maximize torque and mid range power which the BBF has the potential to generate copious quantities of.

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