12/1/2007
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Figure 1 KA24 Nissan SOHC block may have timing c...
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Figure 2 The use of a screened gasket between the...
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Figure 3 “Warranty Buster” intake and EGR gasket ...
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EngINtel: A Stack of Gifts Almost as Satisfying as Chestnuts Roasting on an Open Fire
By Roy Berndt
At this time of year, let me be the first one to to give you a gift and it’s one you’ll likely use again and again. Many of you may have not seen this issue, but once it bites you, you will always remember the Nissan KA24 engine series in the SOHC configuration.
The engine is actually a pretty darn good engine (which compounds the problem) yet if it has a weak link it is the big long timing chain and tensioner system in the front of the block. When the timing chain, guides and tensioner get high miles and wear the chain can actually start rubbing against the front of the block (Figure 1).
The wear actually looks as though it is a machined area and you may over look the big grooved area. But when the chain cut/rubs into block long enough it may actually break into the water passage (Figure 1).
More often than not when this situation occurs the chain has trashed the front cover as well and if there was coolant in the oil the cover gets the blame.
So take heed when you encounter the KA24, 2.4L SOHC Nissan engine for remanufacturing: there may be a hidden problem that can easily get over looked. Make certain that you inspect the front of the block and if there is any chain rub groove you better make certain that enough casting thickness remains not to end up with a coolant breach.
Back in September, I wrote an article titled “Nightmare on Ford Street” that talked about the 1.9L and 2.0L Ford Escort and 2.0 Ford Focus engines. I described the extremely high rate of instantaneous failures due to debris in the manifold from the original failure, thus contaminating the new install.
Well, the entrepreneurial spirit of those within this industry never ceases to amaze me, and in particular that of Doug Anderson. After reading the article Doug contacted me about sending him both the intake and injector/baffle manifolds. A few days later he expressed excitement about what he was convinced could be a solution to the debris contamination situation on initial start up. He suggested putting a screen between the intake manifold and the injector manifold (Figure 2); thereby preventing debris from being “sucked” into the engine. Skeptic I am, I’m thinking, “Sure, a screen will work for about a day!”
Well, apparently this is not new technology. This type of screened intake manifold gasket has been used in marine applications for that exact purpose; eliminating foreign objects from getting into the engine via the intake manifold.
Enter SPM International, a custom gasket manufacturer in Spencer, IA. Ronald Van Pelt started this company in his garage in 1975 and today SPM has two 30,000 sq.ft. facilities, one for manufacturing and one for warehousing. Intake and injector manifolds, along with a standard new gasket were sent to SPM and in less than three weeks we saw a prototype screen gasket (Figure 3), which I found amazing. The gasket that you see in Figure 3 is for the 1.9L Escort engine and will be installed on a vehicle to verify no impact on any of the combustion control systems. Once that has been verified the next step is to make the 2.0L Escort and 2.0L Focus gaskets and bring these engines back on line with a warranty buster intake gasket.
In the process of the development it became obvious that the EGR port could also distribute debris so a gasket was made for it as well. I will keep you posted of the results and updates on availability of all the gaskets.
With the holiday season upon us I figured there was no better way to end the year than with one of those unexpected feel-good surprises. It’s kind of like getting your first Swiss army knife with 15 different things jammed into it.
This new “screen” gasket is the culmination of interaction that changes an industry. This product was a number of us hooking up and helping each other to solve a problem that everyone in the industry benefits from!
Could this be an attitude and action for all of us to act upon for the New Year? Best wishes to you all.