Hurley Engine Failure- Autopsy

[Jonathan_F]

Hi. I bought a Mazda RX7 Twin turbo last december. It had a £3.3k street ported Hurley engine, high flow twins from Turbo Technics, HKS intercooler, Apexi PFC, Dragon straight through system and downpipe and HKS twin alloy hard pipe setup.
Initially the car was very quick indeed. The engine had completed 1500 miles and had been mapped at WGT.
After another 3000miles it became very sluggish, hard to start and temperamental.
This thread will be a story explaining what went wrong and what I have learnt. Please do not post on it unless you have some vital thoughts as it could become rather too long and I\'d like it to be a good piece of reference.

I should explain that I am a Design Engineer at the only UK owned and built motorcycle manufacturer and i have some usefull experience in engine building gained on VW piston engine building.

What happened?
The engine was fitted and run in. Hurleys serviced the engine at 1500miles and I have the warranty certificate.
At some point the induction and exhaust parts were fitted and the turbos were sent to turbotechnics for modification. The car was rolling roaded with a new PFC at WGT and about 300BHP was produced.
The owner was not happy and WGT pronounced the engine was not good.
On return to Hurleys the car was compression tested OK and because the warranty had been voided (understandably) there was nothing that could be done.
After a while and many checks on the rest of the engine systems the owner sold the car to me. Neglecting to mention he thought is was not a strong engine!!
After purchase I gave the car the reaming of its life for many a mile and noticed a few problems.
Above 6.5k rpm the boost creeped slowly from 0.9 to 1.2 bar and sometimes the car cut out and banged. I thought this most exciting! :2eek
Then a coolant hose blew and the coolant level sensor was faulty so the car got quite hot. I replace the hose and another blew. Car overheated again. Then the third small bore coolant pile blew and the car overheated again! All in one month.
On close inspection the hoses had either had screwdrivers down them or been ripped off stretching the 15 year old rubber. Its unbelievable that Hurleys don\'t replace these hoses. They do not have to be formed hose. They cost about £3 to replace . I urge everyone to replace these ASAP.
The pipes are: to and from the throttle body and a short hose from the back of the waterpump housing just behind the filler cap.

The car now became near impossible to start hot and difficult when cold. The low coolant levels had lead to the pump being starved and the coolant system failing. Rotor and housing temperatures would of soared and this tempered the apex seal springs reducing sealing. Detonation occured also flattening one seal pair completely flat!

At this point I had learned enough to realise the injector readings and boost creep were also shortening the engines life. The car still had standard 550/850 injectors and I was seeing 80% duty at 6k rpm. This is the limit you ever want to reach as the injectors become non-linear at this point. I should like to state at this point that Pip (WGT) informed the owner that the car needed bigger injectors and better fuelling.
The boost creep was caused I believe by Turbotechnics..more to come.

Jon

[John Yorke]

Interesting....... would like to know more before any comment though.

[20B_boy]

The boost creep was caused I believe by Turbotechnics..more to come.

They were given turbos to make flow more? in which case they did good! You cant blame them for making the turbos out flow the stock turbo packs wastegate, can u?

[Jonathan_F]

There was initially a serious boost creep problem. The wastegate area of the castings were in poor condition. This was repaired by TTechnics with steel inserts. Unfortunately the ID of these inserts was smaller than the original casting and the wastegates were incapable of bypassing enough exhaust gas to allow boost control. As I understand it Pip informed TT of the problem and these inserts were machined out. However, when I received the car the wastegates were still incapable of achieving boost control. If a baffle plate was placed in the exhaust then boost control became stable. Which supports the argument.
20B boy. TT were providing a turbo package to a customer. The product was uncontrollable. Not an ideal solution and one that was never rectified properly. The point of this post is to educate not blame.
At this point the exhaust manifold started leaking and I took the car off the road and removed the engine. I shall explain my findings tomorrow. Thanks for reading.

[deanflowers]

As said before my hurley engine was not good either, the hoses that need replacing were not and some were perished and brittle, there was a fuel leak, a couple of oil leaks and the AST tank had been repaired with fibreglass.  The hose from the brake servo to the inlet manifold which has a valve fitted had been replaced with a straight pipe.

Also i have a receipt stating a brand new engine was fitted into the car, and this is how the car was sold to me by the previous owner, but it has truned out to be a rebuilt engine.  Due to the problems i had with the engine and the fact that hurleys didnt want to put it righti took it elsewhere for its 5,000 mile service therefore my warranty was voided.  The bill for this new engine to be fitted was almost £4000 which i\'m glad i didnt pay

[tailz]

I made the mistake of going to Hurley Engineering for around 4/5 months (spend thousands) and it wasn\'t until I put 2+2 together and did some further investigating that I realised they were the source of all my problems.

I found WGT and have not looked back since.

Perhaps it\'s that simple?!

[gsb876]

Have heard from a few people about Hurleys not exactly being very professional or competent so these findings so far aren\'t suprising, although a few have had no probs with them ie JohnF who has a hurley engine without fault so far so not all doom and gloom but quite close  :3Confused

[Martiny]

Problem number 1 = Hurleys!
Problem number 2 = Turbo Technics!!

[johnf]

"ie JohnF who has a hurley engine without fault so far so "

Did blow Sept last year after I\'d owned it for tow years Gurj, but 2 years ain\'t bad. Not great either..

John

[gsb876]

"ie JohnF who has a hurley engine without fault so far so "

Did blow Sept last year after I\'d owned it for tow years Gurj, but 2 years ain\'t bad. Not great either..

John

Didn\'t know that John,in which case they are rubbish, 2 yrs isn\'t nearly close enough to being acceptable  :confused:

[John Yorke]

Not wishing to upset the apple cart, is there anyone brave enough to sing the praises of Hurley\'s?
Having owned my rotary for getting on for 6 years and Hurley have been trading for far longer than that surely there must be some positive feed-back, otherwise you would have thought they would have stopped trading by now???
As we all know the best of them [vendors] get it wrong from time to time, so there MUST be some satisfied customers surely?

[sadgoth]

I had a Hurley engine in my FC, threw a tip in a BIG way! Still, I bought the car with 30k on the engine and the rebuild had been done over 5 yrs previously so didn\'t make any odds as the rebuild was in the plan at some point! Still I have heard one or two negative things about them as well - won\'t be putting them in writing as heresay shouldn\'t be spread on forums IMHO!

[20B_boy]

What mileage was on the engine out of interest John?

[antnicuk]

if my engine lasted 2 years i would be over the moon!!!

i\'m slightly curious and dont want to start an argument but...... why is it when Hurleys is mentioned its a free for all slag off but as soon as its one of the (lets say)  popular tuners,  the thread is closed and dissapears!   Not really fair, and the only thing i can think of is Hurleys arnt a supporting vendor.  Although the reason for thread closure is fear of court action not because they are a supporting vendor ( i am not sticking up for hurleys as i know their history)

Sorry for the thread hijack John B but i feel that our opinions of service providers should be aired.  Thats how you find people who provide a good service.

[tailz]

I agree but think you may have misinterpreted John\'s angle - I took it to be a fair question........if anyone has had a good experience of Hurleys, let us know. There is no unfair opinion there - if they have produced the goods for someone, we should know........but likewise (and from my own experience) if they have provided poor service, people again should know.

Unless I am missing a point somewhere, I think we all want the same thing....don\'t we?!